brick (repaired)

CA104 MATERIALS FOR BUILDING CONSTRUCTIONBRICK

INTRODUCTIONFACTS ABOUT BRICKSTYPE OF BRICKCLASSIFICATION OF BRICKSCHARACTERISTIC OF GOOD BRICKSSIZE OF BRICKSTYPE OF CUT BRICKMORTARTERMINILOGIES IN BRICKLAYINGBRICK BOND

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MORTAR JOINTING AND POINTINGBRICKS IN BUILDING CONSTRUCTION

INTRODUCTION

Figure 1.1: Ordinary clay brick

The word brick used to describe a small block ofburned clay of such size that it can beconveniently held in one hand and it is slightlylonger than twice its width. The great majorityof bricks in use today are made from clay,although bricks can be made from sand and limeor concrete.

A brick is a block, or a single unit ofa ceramic material used in masonry construction,usually stacked together, or lay using variouskinds of mortar to hold the bricks together andmake a permanent structure as in Figure1.1. Bricks are typically produced in common orstandard sizes in bulk quantities. They havebeen regarded as one of the longest lasting andstrongest building materials used throughouthistory.

The standard brick size is 215mm x 102.5 mm x 65mm. With a 10 mm mortar joint the working sizebecomes 225 x 112.5 x 75 mm. bricks may bemanufactured to other shapes and sizes and areusually known “specials”.

Bricks are the only man-made building materialsthat testify to their use since the early humancivilization. With their attractive appearancesand superior properties such as high compressivestrength and durability, excellent fire andweather resistance, good thermal and soundinsulation, bricks are widely used for building,civil engineering work, and landscape design.

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FACTS ABOUT BRICKSBrick is considered by building professionals tobe one of the most environmentally friendlybuilding materials on the market – and it’s beenon the market for a long time! The first knownformed bricks date back to 7,500 BC in the UpperTigris area of modern-day Turkey.

So what is brick, and how is it made?

Bricks are:1. Rectangular blocks, most commonly made

from clay, shale, slate, calciumsilicate, concrete or quarried stone

2. Heated at high temperatures3. Used as building or paving material

Bricks made from clay are the most common. Theclay is mixed with sand and then mixed withwater. Then, the clay is pressed into steelmoulds and heated at 1,000° centigrade, whichlocks in the strength of the brick.

Here are some fun facts about bricks:

1. Bricks are great insulators. They store heatenergy from the sun during the day andrelease heat for several hours after the sunhas set. In hot climates, this thermal lagcan translate into energy savings andincreased comfort for the occupants.

2. Brick is known for its durability – it canwithstand severe wind and extreme weatherconditions.

3. The Great Wall of China, constructed around210 BC, is made of 3,873,000,000 individualbricks.

4. The natural color of a brick is determined bythe mineral content of the clay used. Forexample, a red brick is made of clay withhigh iron content. A pale color brick mostlikely had higher lime content in the clay.

5. In addition to the mineral content of theclay, a brick’s color can also be influencedby the temperature when firing – the higherthe temperature, the darker the brick.

6. In 2007, a new type of brick was inventedusing fly ash, a by-product of coal powerplants.

7. Brick creates very little waste whenmanufactured. Mining one pound of clay yieldsnearly one pound of brick, with only slightmoisture and mineral loss occurring in theheating process.

TYPE OF BRICKCLAY BRICKSClay brickwork is made from selected clays thatare molded or cut into shape and fired in ovens.The firing process transforms the clay into a

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building component with high compressivestrength and excellent weathering qualities,attributes that have been exploited formillennia to build structures ranging fromsingle-storey huts to enormous viaducts.

Clay bricks are readily available, massproduced, thoroughly tested modular buildingcomponents. Their most desirable acoustic andthermal properties derive from their relativelyhigh mass. Clay bricks are generally affordable,require little or no maintenance and possesshigh durability and load bearing capacity.

PERFORMANCE SUMMARYAPPEARANCEClay brickwork is available in a wide variety ofnatural colors and textures derived from firedclay used in combination with cement mortarjoints of various colors and finishes. 1. Bricks remain stable and color-fast and do

not need to be rendered or painted. 2. Clay brickwork is most commonly used uncoated

to display the richness and texture of thematerial.

STRUCTURAL CAPABILITYThe high compressive strength of fired claybricks has been exploited for millennia to build

structures ranging from single-storey huts tomassive public buildings and enormous bridgesand viaducts.

Clay brickwork walls can support relatively highloads such as suspended concrete slabs. Claybrickwork is commonly used in four storeyconstruction and with suitable detailing can beused for load bearing walls in much higherbuildings. Clay bricks are manufactured underclose controls to the requirements of means ofdetermining the strength of clay brickwork wallswhen subjected to horizontal loads resultingfrom wind, earthquake or fire.

THERMAL MASSClay brickwork has high thermal mass. If abuilding with internal clay brickwork walls andconcrete floors is subjected to a heating andcooling cycle that crosses the comfort zone, thebrickwork and concrete will maintain arelatively stable level of heat energy for anextended period. In summer, they will remainrelatively cool and in winter, the same buildingwill remain relatively warm.

REVERSE BRICK VENEERConventional brick veneer construction placesthe high mass of brickwork on the outside of thebuilding, where it contributes little to thethermal performance of the building and fails totake maximum advantage of the inherent

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properties of brick other than its capacity forlong life and low maintenance. Despite itspopularity in the mainstream marketplace,conventional brick veneer is not an idealconstruction system for climate responsivedesign.

On the other hand, reverse brick veneer, inwhich the brickwork is the inside skin of anotherwise conventional stud framed construction,takes advantage of the thermal mass propertiesof clay brickwork and can result in highperforming buildings with lower than averageenergy demands for both heating and cooling.

INSULATIONClay brickwork, combined with internal andexternal air films and a cavity, has moderatethermal resistance. The thermal resistance ofclay brick veneer or cavity walls can be greatlyenhanced by adding foil or bulk insulation.

SOUND INSULATIONDue to their mass, clay bricks provide excellentsound insulation, particularly for low frequencynoise.

TOXICITY AND BREATHABILITYClay bricks are inert and are not prone to offgassing of volatile materials. Clay brickworkand its constituents are non-toxic, however whenhandling cement (used in the mortar) or cutting

brickwork with a masonry saw, manufacturerssafety procedures must be observed to minimizethe risk of skin irritation and lung damage.

DESIGN OF CLAY BRICKWORK FOR FIRE

Fireresistanceperiod

(minutes)

Requiredmaterial

thickness forinsulation

(mm)

Maximumslenderness

for structuraladequacy (mm)

30 60 25.060 90 22.590 110 21.0120 130 20.0180 160 18.0240 180 17.0

Table 1.1: Design of clay brick for fireresistance

FIRE RESISTANCEClay bricks are an excellent medium forachieving fire resistance. Clay brickwork doesnot burn when exposed to bushfire and can helpprotect the more combustible items inside ahouse as shown in Table 1.1.VERMIN RESISTANCEClay brickwork consists of dense inorganicmaterials that do not harbor vermin. Termiteresistance may be achieved in a variety of ways,

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including proprietary termite barriers developedfor use with clay brickwork.

DURABILITY AND MOISTURE RESISTANCEClay brickwork walls resist the penetration ofrainwater, including wind-driven rain, althoughthey are not completely waterproof. Somemoisture may eventually soak through the mortarjoints. For this reason external clay brickworkis generally constructed as either cavitywalling (two leaves of brickwork separated byties) or brick veneer (one leaf of brickworkseparated from, but tied to a structural frame –may be reversed).

Detailing for clay brickwork needs toincorporate:1. Damp-proof courses.2. Flashings.3. Weep holes.

ENVIRONMENTAL IMPACTSClay brick manufacture uses energy but theinvestment of embodied energy is repaid by thelongevity of the material.

Clay brick have:1. Long life 2. Low maintenance requirements.3. Highly recyclable making them a potential

sustainable form of construction.

4. Clay bricks can often be reclaimed for re-usewhen a building is demolished. After cleaningthey can either be directly re-used as bricksagain, or they can be crushed for making pathand road surfaces.

5. Because of their inert, inorganic nature,another use for crushed clay bricks is aspart of the mix for the growing medium ofextensive green roofs.

BUILD ABILITY, AVAILABILITY AND COSTAs a result of the long history of cavity brickand brick veneer construction, there is a hugebody of knowledge and experience on constructionstandards and techniques.

Clay bricks are manufactured throughout ourcountry and are available at competitive pricesthroughout the whole of Malaysia. Even in remoteareas, clay bricks can be supplied at moderateprices due to the wide availability of trucktransport and back-loading opportunities.Consideration should be given to transportenergy costs for any long-distance movement ofheavy material.

TYPICAL DOMESTIC CONSTRUCTIONTYPICAL DETAILSStandard set by government under BS or MSprovide the regulatory framework for the designand construction of clay brickwork. Many of the

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brick manufacturing companies publish designmanuals and standard details.

FOOTINGSFor clay brickwork houses, concrete footings andconcrete raft slabs should comply with standard(BS) designed for slabs and footings. Thisstandard has been based largely on the behaviorof clay brickwork houses. Footings for brickveneer buildings are generally smaller than thecorresponding footings for cavity brickwork.

FRAMESFor brick veneer and reverse brick veneerhouses, frames provide the required strength andstability.

DOMESTIC METAL FRAMINGIn architecturally designed homes the use offrames and clay brick walls may more freelyexploit the qualities of bricks to achieveparticular design outcomes.

LOAD BEARING WALLSCritical to the function of any building is theability of the walls to support suspended floorsin addition to the roof and walls in the storeysabove. In most cases, the inclusion of concretefloor slabs dictates the use of load bearingmasonry.

FIXINGSMajor anchorages (such as roof tie-downanchorages) should be built into brickworkduring construction. For high wind uplift,anchorages should pass down the brickwork cavityand be tied into supporting concrete slabs orfootings. Windows and doors may be built intobrickwork by setting the attached ties in themortar joints.

Minor anchorages (such as hanging light loadsfrom walls) may employ any of the wide range ofcommercially available proprietary mechanical orchemical anchors. These are set in holes drilledusing a hammer drill of the appropriate size. Ifset into brick rather than mortar, higheranchorage strength can be achieved.

OPENINGSMost commercially available doors and windowsaremanufactured to be compatible with claybrickwork,either in veneer or cavity construction.

FINISHESExternal face clay brickwork capitalizes on thebroad variety of colors, textures and finishes,mixed and matched with colored or plain mortarsin struck, ironed, pointed or raked joints.

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Clay brickwork is often used for internalfeature walls – a particularly appropriateapproach for reverse brick veneer construction.Internal brickwork, load bearing walls,firewalls and acoustic partitions may also bepainted, rendered or sheeted with plasterboard.

CALCIUM SILICATE BRICKS (SAND-LIME)The calcium silicate bricks are flint or limebricks which are whitish when steam hardened inan autoclave (they aren't fired like clay), butthese are available in many colors because theypigment well.

They absorb moisture easily, so must never belaid with a mortar that doesn't contain aplasticizer. They can be used in just the sameway as clay bricks. Like engineering bricks,they are also more regular in shape and veryless in size than ordinary bricks.

The raw materials for calcium silicate bricksinclude lime mixed with quartz, crushed flint orcrushed siliceous rock together with mineralcolorants. The materials are mixed and leftuntil the lime is completely hydrated; themixture is then pressed into moulds and cured inan autoclave for two or three hours to speed thechemical hardening.

The finished bricks are;1. Very accurate and uniform 2. Sharp arises that need careful handling to

avoid damage to brick (and bricklayer). 3. The bricks can be made in a variety of

colors, white are common but pastel shadescan be achieved.

4. It has lower embodied energy than cementbased man-made stone and clay brick.

CONCRETE BRICKSConcrete bricks are manufactured in the samesize as clay bricks. They tend to be moreconsistent in shape, size and color than claybricks and come in variety of colors andfinishes as in Figure 1.2 and Figure 1.3.Appearance and properties vary betweenmanufacturers, although the concrete brick doeshave a different appearance from clay bricks,which extends the choice available.

Concrete brick is a very effective way to make astrong first impression. When people walk up ordrive by a home with concrete brick, secondglances are common reactions.

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Figure 1.2: Several form of concrete bricks.BENEFIT1. It’s striking visual qualities. 2. They deaden exterior noise, giving you and

your family a buffer from traffic noise,airplanes flying overhead and other variousdisruptions.

3. Fire protection is another benefit ofconcrete brick. Giving your family, and thefire department, extra time is never a badthing.

4. You won't have to worry about maintenancewith concrete bricks. Kiss those weekends ofstripping and repainting wood siding goodbye.

5. Concrete brick walls can improve the thermalmass qualities of your exterior walls, thusimproving your energy bills.

DESIGNThe requirements for good performance from aconcrete brick wall include:

1. A foundation which will handle the weight ofthe brick veneer

2. A well-braced back-up wall which will handlethe veneer load

3. Proper attachment to the back-up wall.4. Proper design and detailing of expansion

joints, flashing, and drainage5. Proper use of materials6. Good workmanship during construction

STYLESConcrete brick is manufactured in various colorsand patterns as shown in Figure 1.4. The type offinish is even an option; smooth, sandblasted,or stone pattern.

The concrete used to produce the bricks can beanythingfrom regular aggregate concrete to variousmixtures oflightweight aggregates. They are usually coloredwith iron oxide pigment at the surface, or thepigment is present throughout the mixture.

Chances are there is a brick available thatmeets your specifications.

MORTARLESS BRICKA new exterior wall system uses concrete brickscast in special shapes which require no mortarand can be installed by anyone with basic

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carpentry skills. The system provides homeownerswith the effective look of real brick exteriors.

The dimensions and appearance of the brick facesare similar to traditional split-faced bricks,and like bricks used for conventional veneerwalls, they are installed in staggered rows.Hidden from view is the unusual shape of thecast block, which allows shingle-likeoverlapping. Because the system does not requirefooting or mortar, it can be used on new orexisting buildings. Installers stack the blocksin rows and screw them to vertical furringstrips attached to the wall sheathing.

The furring strips provide a positive connectionand create an air space, allowing the veneersurface to breath and providing drainage for anymoisture that may penetrate. Thermal insulationcharacteristics are about the same as commonface brick and each unit weighs just over 4 lbs.Because of the interlocking shape of thematerials, the system requires no mortar and canbe installed by a contractor, handyman orhomeowner with basic woodworking and layoutskills. Like traditional split-face brick, thesystem is strong and durable and will not dent,chip or fade in color.

This brick has a molded bark texture face.

Bricks are also available with a roughestate texture face.

Figure 1.3: Concrete brick with textured face

Figure 1.4: The pictures above, concrete brickcomes in many styles. This can help you blend

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a house in with its natural surroundings orneighboring houses.Less expensive than other types of brick, themortarless brick has been on the market for afew years. Thanks to an installation system thatuses screws, it’s easier to install thanconventional brick, but harder than vinyl andaluminum.

Figure 1.5: Mortarless brick in isometric, faceand side view.

Figure 1.6: The interlocking shapes ofmortarless brick.

Figure 1.7: Clinker brick’s form and usage assbuilding construction.

CLINKER BRICKClinker bricks are partially vitrified brickstones used in the construction of buildings.Clinkers are burnt under temperatures so high

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that the pores of the fuel property are closedby the beginning sinter process. Thus they areconsiderably denser and therefore heavier thanregular bricks. Clinkers hardly take up waterand are very resistant.

Clinker bricks were often in combination withrocks in walls, foundations, and chimneys as inFigure 1.7.

The name "clinker" is also used for the hardenedresidue of coal fires, which can have a similartexture.

FIRE BRICKA fire brick, firebrick, or refractory brick is:1. A block of refractory ceramic material used

in lining furnaces, kilns, fireboxes, andfireplaces. A refractory brick is builtprimarily to withstand hightemperature, but will also usually have a lowthermal conductivity for greater energyefficiency.

2. Dense firebricks are used in applicationswith extreme mechanical, chemical, or thermalstresses, such as the inside of a wood-firedkiln or a furnace, which is subject toabrasion from wood, fluxing from ash or slag,and high temperatures.

3. In less harsh situations, such as a naturalgas fired kiln, more porous bricks are abetter choice. They are weaker, but they aremuch lighter, easier to form, and insulatefar better than dense bricks.

4. Firebricks should not spall under rapidtemperature change, and their strength shouldhold up well during rapid temperaturechanges.

CHARACTERISTICS OF FIRE BRICKMANUFACTURE In the making of firebrick, fireclay is baked inthe kiln until it is partly vitrified, and forspecial purposes may also be glazed.

Also available are firebrick "splits" which arehalf the thickness and are often used to linewood stoves and fireplace inserts. Thedimensions of a split are usually 9" × 4½" ×1¼".

COMPOSITION Fire bricks usually contain 30-40% aluminumoxide or alumina and 50% silicon dioxide orsilica. They can also be made of chamotte andother materials. For bricks of extremerefractory character, the aluminum oxide contentcan be as high as 50-80% (with correspondingly

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less silica), and silicon carbide may also bepresent.

Figure 1.8: Form and color of fire brick.

HIGH TEMPERATURE APPLICATIONS The silica firebricks that line steel-makingfurnaces are used at temperatures up to 1650°C(3000°F), which would melt many other types ofceramic, and in fact part of the silicafirebrick liquefies. HRSI, a material with thesame composition, is used to make the insulatingtiles of the space shuttle.

LOWER TEMPERATURE APPLICATIONS A range of other materials find use asfirebricks for lower temperature applications.Magnesium oxide is often used as a lining forfurnaces. Common red clay brick are used forchimneys and wood-fired ovens.

TYPE OF FIRE BRICKSREFRACTORY CLAY BRICKClay bricks use Chamotte that the fire clay is calcinated as the main material. These bricks consist of fire clay binder. The chemical components of these are SiO² and Al²O³ as in Figure 1.10.

CORUNDUM FIRE BRICK Corundum brick (Figure 1.11), has the followingfeatures: 2.1. Good anti-acid.2.2. Anti-alkali slag in furnace and anti-metal and anti- glass solution corrosion. 2.3. Corundum brick keeps stable quality working

in oxidative atmosphere.

PHOSPHATE BRICK Established in 1984 by manufacturer and exporterthat is concerned with the design, developmentand production of fire bricks and refractorymaterials as in Figure 1.12.

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MAGNESIA FIRE BRICK (Figure 1.13)

SK-30, SK-32, SK-34, SK-36 – Clay bricks use Chamotte that the fire clay iscalcinated as the main material (Figure 1.9).These bricks consist of fire clay and binder.The chemical components of these bricks are SiO²and Al²O³.

FLY ASH BRICKSA Clay brick, which was the primary wallmaterial, is now being replaced by fly ashbricks, which are hi-tech well-improved qualityproducts. They are competitive in comparison tothe conventional clay bricks and provideenormous indirect benefits. The country can gaina lot

Figure 1.9: Chamotte clay bricks series SK-30, SK-32, SK 34 and SK 36

Figure 1.10: Refractory clay fire brick

Figure 1.11: Corundumfire brick

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Figure 1.12: Phosphate brick.

Figure 1.13: Magnesia fire brick

by gainful utilization of fly ash bricksresulting in conservation of natural resourcesas well as protection of environment.

COMPOSITION:1. Fly ash2. Cement3. Sand4. Water

SOURCES OF FLY ASH:Fly ash contains CO2 emitted from thermal powerplants,industries using coal as a fuel emits unwantedash and smoke from which fly ash is produced. Inall the power plants and industries, theyseparate the fly ash by using the cycloneconverter. This fly ash is then used as a rawmaterial for manufacture of bricks.

NATURE OF POLLUTION CAUSED BY FLY ASH:Fly ash causes severe pollution of air andwater, and its disposal gobbles up large tractsof land. Well-planned programs for propermanagement of fly ash are therefore beingundertaken to enhance the use of fly ash invarious applications, so that our already

perilously imbalanced environment can beprotected.

RECLAIMEDReclaimed bricks are given to the bricks thathave been salvaged from old buildings. They area variety of ages, shapes, sizes and colors. Ifyou don't know what you're looking for, it isimportant to consult a specialist to help, asthese bricks can be expensive and tiresome toclean, prepare and sort. There is often a lot ofwaste with reclaimed bricks - if you want thelook but not the hassle, try looking atreproduction reclaimed bricks.

CLASSIFICATION OF BRICKSClay bricks can be classified according to theirvarieties, qualities, and classes.

COMMON BRICKSCommon burnt clay bricks, which are accepted foruse in general brick work with no special claimfor attractive appearances. Walls built withcommon bricks require rendering or plastering.

FACING BRICKS Quality burnt clay bricks, which give attractiveappearance in their color and texture like in

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Figure 1.14. It is used without rendering,plastering, or other surface treatments.

Facing bricks come in a variety of colors andtextures for they are made to be displayedindoors and outdoors. Also called stocks, they arecapable of bearing heavy loads. If classed asordinary quality, it means they can be used formost projects, but in very exposed conditionsoutdoors will need to be protected by

a damp proof course at ground level (either acourse of engineering bricks, or a layer ofbituminous felt) or with a coping above toprevent the bricks becoming saturated with rain.

Without this protection they are liable to beaffected by frost which would causedisintegration. Special quality facing bricksare suitable for use in exposed places or wheregreat strength is needed, e.g. for paving,retaining walls, garden walls and steps.

The role of bricks has evolved greatly; modernclay facing bricks are a subtle combination ofaesthetics, economy and tradition. As a resultthey have come to be recognized as one of themost important material choices on anycommercial or domestic project. Cladding abuilding in a quality facing brick provides notonly an attractive facade, but also ensures thelong term future of the structure. It is even

true to say that some facing bricks become moreattractive with influence of time.

Facing bricks are a safe and long lastingbuilding material. Their unique absorptionproperties contribute to a healthy livingclimate, whilst their strength ensures thatongoing maintenance costs are negligible. Inaddition, when used in cavity wall construction,facing bricks can also provide a valuable andeffective barrier against noise pollution.

LOADBEARING BRICKSLoadbearing bricks, which can be either commonor facing bricks.

A load-bearing wall (or bearing wall) is a wallthat bears a load resting upon it by conductingits weight to a foundation structure. Thematerials most often used to construct load-bearing walls in large buildings are concrete,block, or brick.

Wire-Cut Rock-Face Super Wire-Cut Cream

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Super Red Red

Smooth-FaceRed Rock-Face Cream Smooth-Face

BrownFigure 1.14: Varieties of facing brick

ENGINEERING BRICKSEngineering bricks as Figure 1.15 are bricksburnt at exceedingly high temperatures. Theypossess a dense and strong semi-vitreous bodyand conform to the defined limits for strengthand water absorption. They are primarily used incivil engineering works that require high loadbearing capacity, good damp-proof,

Engineering bricks are:1. Manufactured to be denser and stronger than

ordinary facing bricks.

2. They are supplied in accordance with twodifferent classifications, Class A and ClassB. This is based on minimum compressivestrength and maximum water absorption notfalling below 70 N/mm2 - 4.5% and 50 N/mm2 -7% respectively.

3. Engineering bricks are designed for use wherestrength and low levels of water absorptionare paramount; traditionally this may be onapplications such as load bearing walls,retaining walls, foundation courses (thusproviding a damp proof course for a wall orplanter), or for ground works.

Figure 1.15: Engineering bricks as standard comein 31/5 in x 4 in x 8 in (8.13 cm x 10.16 cm x20.36 cm). Engineering bricks are perfect foroccasions when strength is more important thanappearance and chemical resistingcharacteristics.

DAMP PROOF COURSEClay bricks of specified low water absorptionused at the base of a wall (minimum two courses)to resist the upward movement of ground water.Their use is recommended for free standing wall

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where otherwise a sheet of damp proof course(DPC) material would create a plane of weaknesscausing the wall to be vulnerable to lateralforces.

INNOVATIVE BRICK There are also innovative brick manufacturerswho have begun to make brick using materialslike: 1. Sewage sludge

The sewer sludge material can be mixed withclay and sent through the manufacturingprocess, resulting in a brick equally asstrong and attractive.

2. Petroleum-contaminated soils. Petroleum-contaminated soils are hazardousfor the environment and human and animalhealth; manufacturers have designed a way ofcombining the petroleum-contaminated soilwith clay. When fired at very hightemperatures, it creates brick that is freefrom hydrocarbon contamination.

CHARACTERISTIC OF GOOD BRICKS

FREE FROM LUMPS OR FLOWS1. Freedom from Flaws or Lumps. - Good building

brick should be sound, free from cracks andflaws, also from stones, or lumps of anykind.

2. Lumps of lime, however small, are especiallydangerous; they slake when the brick isexposed to moisture, and split it to pieces.

3. A small proportion of lime finely divided anddisseminated throughout the mass is anadvantage, as it affords the flux necessaryfor the proper verifications of the brick.

4. In examining a brick, lumps of any kindshould be regarded with suspicion and tested.

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SHAPE AND SURFACE1. In order to ensure good brickwork the bricks

must be regular in shape and uniform in size.2. Their arrises (or edges) should be square,

straight, and sharply defined.3. Their surfaces should be even, not hollow;

not too smooth, or the mortar will not adhereto them.

ABSORPTION1. The proportion of water that a brick will

absorb is a very good indication of itsquality.

2. Insufficiently burnt bricks absorb a largeproportion and are sure to decay in a shorttime.

3. It is generally stated in books that a goodbrick should not absorb more than 1/15 of itsweight of water.

4. The absorption of average bricks is, however,generally about 1/6 of their weights, and itis only very highly vitrified bricks thattake up so little as 1/13 or 1/15.

TEXTURE 1. Good bricks should be hard, and burnt so

thoroughly that there is incipientverification all through the brick.

2. This may be seen by examining a fractured, orthe surface may be tested with a knife, which

will make hardly any impression upon itunless the brick is under burnt.

3. A brick thoroughly burnt and sound will giveout a ringing sound when struck againstanother. A dull sound indicates a soft orshaky brick.

4. A well-burnt brick will be very hard, andpossesses great power of resistance tocompression.

PROPERTIES AND FUNCTIONAL PERFORMANCESOF BRICK Bricks are made from clay by burning it at hightemperatures. The action of heat gives rise to asintering process that causes the clay particlesto fuse and develops extremely strong ceramicbonds in the burnt clay bodies. Such bonds arehighly stable. As a result, bricks can withstandthe severe weathering actions and are inert toalmost all normal chemical attacks.

STRENGTHBricks are well-known for their high compressivestrength. Their compressive strength depends on:1.1. The raw materials used1.2. The manufacturing process1.3. The shape and size.

Bricks made by a de-aerated extruder and firedto sufficiently high temperature can easilywithstand a compressive pressure exceeding 28

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N/mm2 (4,000 psi). They are suitable for almostall structural building applications

AESTHETIC APPEALBrick possesses the natural and pleasant colorsof burnt clay. Its color formation is achievedthrough a complicate physical chemical reactionduring the firing process. In contrast to colorof stained body, brick color is permanent andwill not be faded during weathering process.Different clay compositions, firing temperaturesor kiln atmosphere can lead to different colorsof the burnt products. By proper control ofthese factors, bricks can be made to exhibitendless variety of natural and attractivecolors.

Besides its richness in color, bricks can bemade to various textures. It is the combinationof color and texture that gives brick suchdistinctive feature which is everlasting andmeadows with age. In view of the high cost tomaintain the appearance of a building, theunique features of brick become an unparalleledadvantage to housing design.

POROSITYPorosity is an important characteristic of brickand the porosity of brick is attributed to itsfine capillaries.

By virtue of the capillary effect, the rate ofmoisture transport in the brick is ten timesfaster than in other building materials.Moisture is released during day-time and re-absorbed during night-time.

The ability to release and re-absorb moisture (a"breathing" process) by capillary effect is oneof the most useful properties of brick thathelps to regulate the temperature and humidityof atmosphere in a house. This distinctiveproperty makes brick an admirable buildingmaterial, particularly suitable for houses inthe tropics. On the other hand, all porousmaterials are susceptible to chemical attacksand liable to contamination from weatheringagents like rain, running water and pollutedair. Porosity of building material is animportant factor to consider in respects itsperformance and applications.

Experiment results show that bricks with waterabsorption rate at 8% are 10 times more durablein resisting salt attack than that with waterabsorption rate at 20%. Well burnt brick has anormal water absorption rate less than 10% incontrast to that of concrete block and cementmortar exceeding 15%. This explains why brickwalls require comparatively minimum maintenancein the course of time.

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To mitigate the adverse effects but at the sametime retain the advantages associated withporosity, the rate of water absorption of facingbricks for masonry brickwork should preferablebe maintained around 10%.

FIRE RESISTANCEBrick is inherent with excellent fireresistance. 100 mm brickwork with 12.5 mm normalplastering will provide a fire-resistance of 2hours and 200 mm non-plastered brickwork willgive a maximum rating of 6 hours for non-loadbearing purposes. Brick can support considerableload even when heated to 1000oC in contrast toconcrete wall at only up to 450oC due to loss ofwater of hydration.

It is a fact that the non-combustibility ofbrick helps to promote its use in buildinghouses against fire. There have been numerousexamples in the past that people chose to usebricks for their houses after a devastating firethat burned down the whole city.

SOUND INSULATIONBrick wall shows good insulation property due toits dense structure. The sound insulation ofbrickwork is generally 45 decibels for a 4-1/2in. thickness and 50 decibels for a 9-in.thickness for the frequency range of 200 to2,000 Hz.

THERMAL INSULATIONBrick generally exhibits better thermalinsulation property than other buildingmaterials like concrete. Perforation can improvethe thermal insulation property of bricks tosome extent. Besides, the mass and moisture ofbricks help to keep the temperature inside thehouse relatively constant. In other words,bricks absorb and release heat slowly and thuskeep the house cool during daytime and warmduring nighttime.

Energy saving of a brick house is remarkable. Astudy commissioned by the Brick Institute ofAmerica had demonstrated that a brick house cansave energy up to 30% when compared to thatbuilt of wood.

WEAR RESISTANCEThe wear resistance of a substance depends onits particulate bonds. Bricks show high wearresistance because of its extremely strongceramic bonds formed by the effect of heat athigh temperature.

EFFLORESCENCEEfflorescence is a phenomenon that soluble slatsdissolved in water are carried, deposited andgradually accumulated on brick surfaces to forman unsightly scum. The soluble salts may beoriginated from the raw material of bricks. But

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in most cases, efflorescence is caused by saltsfrom the external sources such as ground water,contaminated atmosphere, mortar ingredients andother materials in contacts with the bricks.

FLEXIBILITY IN APPLICATIONSBrick is used for an extremely wide range ofapplications in an equally extensive range ofbuilding and engineering structures. Inparticular, it can be used for load bearingstructures which greatly simply the constructionprocess so as to save materials, time and labor.Besides, brick can be make into convenient shapeand size to facilitate the construction work. Itis very flexible and handy in application almosteverywhere.DURABILITYBrick is extremely durable and perhaps is themost durable man-made structural buildingmaterials so far. There has been numerousancient brick-building standing for centuries asa testimony of the endurance of burnt-claybrick.

SIZE OF BRICKFor efficient handling and laying bricks must besmall enough and light enough to be picked up bythe bricklayer using one hand (leaving the otherhand free for the trowel). Bricks are usuallylaid flat and as a result the effective limit on

the width of a brick is set by the distancewhich can conveniently be spanned between thethumb and fingers of one hand, normally aboutfour inches (about 101 mm). In most cases, thelength of a brick is about twice its width,about eight inches (about 203 mm) or slightlymore.

The correct brick for a job can be picked from achoice of color, surface texture, density,weight, absorption and pore structure, thermalcharacteristics, thermal and moisture movement,and fire resistance.

The six surfaces of a brick are called cull,beds, side, end, and face, as shown in Figure1.12. Occasionally you will have to cutbrick into various shapes to fill in spacesat corners and other locations where a fullbrick does not fit. Figure 1.12 shows themore common cut shapes which follow:

OPTIMAL DIMENSIONThe usual ("work") size of a modern brick is 215× 102.5 × 65 mm (about 8.5 × 4 × 2.5 inches). Inthe United States, modern bricks are usuallyabout 8 × 4 × 2.25 inches (203 × 102 × 57 mm) asin Table 1.6.

In England, the length and the width of thecommon brick has remained fairly constant overthe centuries. In the United Kingdom, the usual

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size of a modern brick is 215 × 102.5 × 65 mm(about 8 5 ⁄8 × 4 1 ⁄8 × 2 5 ⁄8 inches), which, with anominal 10 mm (3 ⁄8 inch) mortar joint, formsa unit size of 225 × 112.5 × 75 mm (9 × 4 1 ⁄2 ×3 inches), for a ratio of 6:3:2. In the UnitedStates, modern bricks are usually about 8 × 4× 2 1 ⁄4 inches (203 × 102 × 57 mm).

Some brick makers create innovative sizes andshapes for bricks used for plastering (andtherefore not visible) where their inherentmechanical properties are more important thanthe visual ones. These bricks are usuallyslightly larger, than but not as large as blocksand offer the following advantages:1. A slightly larger brick requires less mortar

and handling (fewer bricks) which reducescost

2. Ribbed exterior aids plastering3. More complex interior cavities allow

improved insulation, while maintainingstrength.

Bricks may also be classified as:1. Solid

Less than 25% perforations by volume,although the brick may be "frogged," havingindentations on one of the longer faces.

2. Perforated

The brick contain a pattern of small holesthrough the brick that remove no more than25% of the volume.

3. CellularContaining a pattern of holes that removingmore than 20% of the volume, but closed onone face.

4. HollowContaining a pattern of large holes thatremoving more than 25% of the brick's volume.

The term "frog" for the indentation on one bedof the brick is a word that often excitescuriosity as to its origin. The most likelyexplanation is that brick makers also call theblock that is placed in the mold to form theindentation a frog. Modern brick makers usuallyuse plastic frogs but in the past they were madeof wood. When these are wet and have clay onthem they resemble the amphibious kind of frogand this is where they got their name. Over timethis term also came to refer to the indentationleft by them.

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Figure1.16: Names of brick surfaces.

Standard Imperial(in) Metric (mm)

Australia 9 × 4⅓ × 3 230 × 110 × 76Germany 9 × 4¼ × 2¾ 240 × 115 × 71India 9 × 4¼ × 2¾ 228 × 107 × 69Russia 10 × 4¾ × 2½ 250 × 120 × 65South Africa 8¾ × 4 × 3 222 × 106 × 73Sweden 10 × 4¾ × 2½ 250 × 120 × 62United Kingdom 8½ × 4 × 2½ 215 × 102.5 × 65United States of America 8 × 4 × 2¼ 203 × 102 × 57

Table 1.2: Standard brick sizes from different countries.

THE BRICK QUANTITIESFor an area of 1 sq. m, the bricks needed are 60and 0.02 cubic meters of mortar. If the area is2 sq. meters, the needed quantity is 120 bricksand the mortar required is 0.05 cubic meters.

300 bricks are needed for an area of 5 sq.meters. 0.12 cubic meters of mortar is required.600 bricks are needed for a 10 sq. meter area.The mortar required is 0.24 cubic meters.

. Figure 1.17: Cut bricks

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TYPE OF CUT BRICKBATA half bat is one half. It is a portion of abrick cut across the width as shown in Figure1.17.

CLOSERA cut brick used to change the bond at quoins,commonly called a quarter bats. It is theportion of a brick cut in such a manner that itsone long face remains uncutQUEEN CLOSERIt is the portion of a brick obtained by cuttinga brick length-wise into two portions or a brickwhich has been cut over its length and is astretcher long and a quarter bat deep as shownin Figure 1.17.

KING CLOSERIt is the portion of brick obtained by cuttingoff the triangular piece between the centre ofone end and the centre of one side or a brickwhich has been cut diagonally over its length toshow a half bat at one end and nothing at theother as shown in Figure 1.17.

BEVELLED CLOSERIt is the portion of a brick in which the wholelength of the brick is bevelled for maintaining

half width at one end and full width at theother as shown in Figure 1.17.

MORTARMortar is a workable paste used to bindconstruction blocks together and fill the gapsbetween them. The blocks may be stone, brick,cinder blocks, etc. Mortar becomes hard when itsets, resulting in a rigid aggregate structure.Modern mortars are typically made from a mixtureof sand, a binder such as cement or lime, andwater. Mortar can also be used to fix, or point,masonry when the original mortar has washedaway.

Mortar is an essential component for successfulbrickwork. It has a profound, but oftenunappreciated, effect on the appearance of thework and has important technical requirements tofulfill.

Mortar is a durable, gap-filling adhesive that: 1. Acts as a cushion to spread vertical loads

evenly down into the brickwork 2. Allows adjustment of the position of each

brick to line, level and plumb, as it is laid3. Sticks the bricks together for stability 4. Forms a seal between them to resist rain

penetration.

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THE FUNCTION OF MORTARMortar is a mixture of materials for jointingmasonry units. It has numerous tasks like:1. It sticks the bricks together to provide

stability - and solidity while holding themapart to spread loads evenly. It compensatesfor irregularity between units when straight,level and plumb walling is laid.

2. It also seals any gaps to resist wind or rainpenetration.

3. Fulfilling its gap-filling adhesive functionit is required to have durability andstrength to suit the application.

4. The physical properties of a mortar depend onthe nature and proportions of itsconstituents.

5. A specifier must select a mortar with theappropriate balance of properties with regardto the 'in service' vulnerabilities andrequirements of the masonry.

The principal constituent of mortar is sandwhich should be 'well graded'. This means thatthere should be an even distribution of particlesizes from the finest to the coarsest - withoutany excess or omission of any particular size.

Sands for mortars are:1. Often referred to as 'builder’s sand',

'bricklayer’s sand' or 'mortar sand'.

2. 'Soft sands' should not be used for mortarsas these contain fine silts and clayparticles which can lead to unacceptableshrinkage movement in the set and hardenedmortar.

3. 'Sharp sands' are also unsuitable becausetheir lack of finer particles causes poorwater retention during application resultingin a harsh unmanageable mortar.

A quantity of compacted sand will have voidswhich even the finest particles cannot totallyfill. With well graded sand the void is one-third of the total volume and this proportiondictates the ideal volume of binder materialused to complete the mortar mix, i.e. the mortarmix is 3 parts by volume of sand: 1 part byvolume of binder.

THE SELECTION OF MORTARGUIDANCE ON DURABILITY Selection of the appropriate mortar for aparticular application requires carefulconsideration of the vulnerability of thebrickwork.

GUIDANCE ON STRENGTH With air-entrained mortars it has been alreadyobserved that the percentage of air content mustbe controlled. Over mixing of these mortarscauses excessive air content and this condition

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prejudices the development of bond andcompressive strength. For this reason,structural engineers generally do not approve ofair-entrained mortars in calculated structuralmasonry.

A popular adage in connection with mortarselection is "the mortar should not be strongerthan the brick". Contemporary guidance seems tooverrule this advice and does so with regard todurability as weaker mortars might not besuitable for the more severe exposure conditionsin which certain low-strength bricks mightthemselves be quite acceptable.

The adage is based on the understanding that instructures prone to settlement or other movementthe use of strong mortars might result incracking of low-strength bricks rather thancracking confined to mortar joints.

TYPE OF MORTAR

ANCIENT MORTARThe first mortars were made of mud and clay.Because of a lack of stone and an abundance ofclay, Babylonian constructions were of bakedbrick, using lime or pitch for mortar. Accordingto Roman Ghirshman, the first evidence of humansusing a form of mortar was at the ziggurat of

Sialk in Iran, built of sun-dried bricks in 2900BC. The Chogha Zanbil Temple in Iran was builtin about 1250 BC with kiln-fired bricks and astrong mortar of bitumen.

In early Egyptian pyramids constructed about2600–2500 BC, the limestone blocks were bound bymortar of mud and clay, or clay and sand. Inlater Egyptian pyramids, the mortar was made ofeither gypsum or lime. Gypsum mortar wasessentially a mixture of plaster and sand andwas quite soft.

In the Indian subcontinent, multiple cementtypes have been observed in the sites of theIndus Valley Civilization, such as the Mohenjo-daro city-settlement that dates to earlier than2600 BCE. Gypsum cement that was "light grey andcontained sand, clay, traces of calciumcarbonate, and a high percentage of lime" wasused in the construction of wells, drains and onthe exteriors of "important looking buildings."Bitumen mortar was also used at a lower-frequency, including in the Great Bath atMohenjo-daro.

Historically, building with concrete and mortarnext appeared in Greece. The excavation of theunderground aqueduct of Megara revealed that areservoir was coated with a pozzolanic mortar12 mm thick. This aqueduct dates back to c. 500BC. Pozzolanic mortar is a lime based mortar,

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but is made with an additive of volcanic ashthat allows it to be hardened underwater; thusit is known as hydraulic cement.

The Greeks obtained the volcanic ash from theGreek islands Thira and Nisiros, or from thethen Greek colony of Dicaearchia (Pozzuoli) nearNaples, Italy. The Romans later improved the useand methods of making what became known aspozzolanic mortar and cement. Even later, theRomans used a mortar without pozzolana usingcrushed terra cotta, introducing aluminum oxideand silicon dioxide into the mix. This mortarwas not as strong as pozzolanic mortar, but,because it was denser, it better resistedpenetration by water.

Around CE 500, sticky rice soup was mixed withslaked lime to make an inorganic−organiccomposite mortar that had more strength andwater resistance than lime mortar.

During the Middle Ages when the Gothiccathedrals were being built, the only activeingredient in the mortar was lime. Since curedlime mortar can be degraded by contact withwater, many structures suffered from windblownrain over the centuries.

LIME MORTAR

Lime mortar is a substance used to bind togetherbrick or stone. It can also be used to fill gapsin masonry. Lime mortar has been used sinceearliest times and variations are known from allover the world.

Lime mortar is a mixture of lime, sand andwater. The lime used for mortar may be fat limeor hydraulic lime (see footnote to the tableabove for the description). Fat lime hardens asit loses its water or absorbs carbon dioxidefrom the atmosphere. Hydraulic lime containssilica, alumina and iron oxide in smallproportions.

When mixed with water, it forms putty which setsand hardens under water. Sand in lime mortaracts as an adulterant, and reduces itsshrinkage.

With the introduction of ordinary Portlandcement (OPC) during the 19th century the use oflime mortar in new constructions graduallydeclined, largely due to Portland’s ease of use,quick setting and compressive strength. Howeverthe soft, porous properties of lime mortarprovide certain advantages when working withsofter building materials such as natural stoneand terracotta. For this reason, while OPCcontinues to be commonly used in brick andconcrete construction, in the repair of older,stone-built structures and the restoration of

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historical buildings the use of OPC has largelybeen discredited.

The speed of set can be increased by usingimpure limestone in the kiln, to form a

hydraulic lime that will set on contact withwater. Such a lime must be stored as a drypowder. Alternatively, a pozzolanic material

Increasing

strength&

improvingduribilit

y

Ability toaccommodatemovement

Category

Cement: lime:sand Masonry cement: sand Cement: sand with

plasticiserI 1:3:0

II 1:0.5:4 1:3 1:3

III 1:1:6 1:5 1:5

IV 1:2:9 1:6 1:7

V 1:3:12 1:7 1:8

Increasing resistance to frost during construction

Better adhesion and resistance to rain penetration

Table 1.3: Table showed category and mixing ratio for certain type of mortar.

such as calcined clay or brick dust may be addedto the mortar mix. This will have a similareffect of making the mortar set reasonablyquickly by reaction with the water in themortar.

Lime mortar is considered breathable in that itwill allow moisture to freely move through itand evaporate from its surface. In old buildingswith walls that shift over time, there are oftencracks which allow rain water into thestructure. The lime mortar allows this moistureto escape through evaporation and keeps the walldry. Repointing or rendering an old wall with

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cement mortar stops this evaporation and cancause problems associated with moisture behindthe cement.

Traditional lime mortar mix is a combination oflime putty and aggregate (usually sand). Atypical modern

lime mortar mix would be 1 part lime putty to 3parts washed, well graded, sharp sand. Othermaterials have been used as aggregate instead ofsand. The theory is that the voids of emptyspace between the sand particles account for a1/3 of the volume of the sand. The lime puttywhen mixed at a 3 to 1 ratio, fill these voidsto create a compact mortar.

If shrinkage and cracking of the lime mortardoes occur this can be as a result of either:1. The sand being poorly graded or with a

particle size that is too small2. The mortar being applied too thickly (Thicker

coats increase the possibility of shrinkage,cracking and slumping)

3. Too much suction from the substrate4. High air temperatures or direct sunlight

which force dry the mortar5. High water content in the lime mortar mix6. Poor quality or un-matured lime putty

Pozzolans can be added to the mix of limemortar. These are substances which when combinedwith lime produce a hydraulic (cementitious)set. They include powdered brick, heat treatedclay, silica fume, fly ash, and volcanicmaterials. The chemical set imparted ranges fromvery weak to almost as strong as Portlandcement.

The lime mortar is used for:1. Slaked fat lime is used to prepare mortar for

plastering.2. Hydraulic lime is used for masonry

construction of chimneys and lightly loadedsuperstructure of buildings. In general, limemortar is not suitable for water-logged areaand damp conditions.

CEMENT MORTARPortland cement mortar (often known simply as cement mortar) is created by mixing Ordinary Portland cement (OPC) with sand and water as in Figure 1.18.

It was invented in 1794 by Joseph Aspdin andpatented on 18 December 1824, largely as aresult of various scientific efforts to developstronger mortars than existed at the time. Itwas popularized during the late nineteenthcentury, and owing to the First World War, by

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http://en.wikipedia.org/wiki/Sand

http://en.wikipedia.org/wiki/Portland_cement


1930 it had superseded lime mortar for newconstruction. The main reasons for this werethat Portland cement sets hard and quickly,allowing a faster pace of construction, andrequires less skilled workers. However, as ageneral rule, Portland cement should not be usedfor the repair of older buildings constructed inlime mortar, which require the flexibility,softness and breathability of lime if they areto function correctly.

Cement mortar is a building compound created bymixing sand and a selection of aggregates with aspecified amount of water. The mortar can beused for a number of applications, such asplastering over bricks or other forms ofmasonry. Sometimes referred to as sand cement,mortar blends today often incorporate differentgrades of plastics to create various types ofpolymer cement mortars.

Mortar has been used for centuries as a means ofadhering bricks or concrete blocks to oneanother. Cement mortar continues to be used inmany different types of construction.Professional building projects often employmortar as the binder between bricks in walls,fences, and walkways. Around the house, cementmortar is often employed to make quick repairsin patio slabs and reset loosened stones orbricks in a walkway or retaining wall.Homeowners sometimes set children’s recreational

equipment such as swing sets firmly in theground, minimizing the chances of the equipmentshifting or toppling while in use.

Cement mortar also makes an excellent medium forcreating a smooth surface to walls made frombricks and other forms of Masonry as in Figure1.19. The mortar is applied with the use of atrowel and then smoothed into position. Often,the application is conducted in more than onecoat, making it possible to slowly achieve acovering that adheres properly to the wallsurface. The mortar may be tinted in order toadd a small amount of color to the façade orpaint can be added as a topcoat at a later date.The amount of water to add to the compounddepends greatly on the ratio and type ofingredients used in the product, as well asprevailing weather conditions and the intendedtask. Most premixed products will enclosespecific instructions for adding liquid to thecontents of the package based on relevantfactors.

CEMENT MORTAR MIX Cement mortar is a building compound created bymixing sand and a selection of aggregates with aspecified amount of water as in Table 1.4. Themortar can be used for a number of applications,such as plastering over bricks (Figure 1.13), orother forms of masonry.

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http://www.wisegeek.com/what-is-a-trowel.htm

http://www.wisegeek.com/what-is-a-retaining-wall.htm

http://www.wisegeek.com/what-are-polymers.htm

http://www.wisegeek.com/what-is-masonry.htm

http://www.wisegeek.com/what-is-mortar.htm


Mortar mix is a combination of cement and sandthat is used to hold together construction typeblocks. When water is added, it becomes aworkable paste that sets hard.

Mortar sand :cement

sand : lime :cement

General building (aboveground)

5:1 5:1:1

General building (belowground)

3:1 6:1:1

Internal walls 8:1 9:2:1

Table 1.4: Schedule shown the combination of sand, lime and cement in mortar mixingCOLORED MORTARNothing looks worse than a repair to pointing,than a mortar mix of the incorrect color, someof the pre-mixed mortar mixes have very highcement content or made with dark sand, and bothwill stand out like a sore thumb if used torepair a wall.

Figure 1.18: Laying brickswith portland cement mortar

Figure 1.19: Mortar mixed inside a 5 gallonbucket using clean water and mortar from a bag.When it's the right consistency as in the photo(trowel stands up) it's ready to apply

Coloured pointing mortars are available in a selection of complimentary colours and can beused to point brick slips and stone slips, aswell as traditional brickwork.

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http://en.wikipedia.org/wiki/File:Brick_and_block_laying.jpg

http://en.wikipedia.org/wiki/File:Mortar_mixed_inside_bucket.jpg


Bag weight: 25kgCoverage: 5-6m² per bag

Natural gray Dark gray Dark brown Sandstone Buff Black

Figure 1.20: Application of colour mortar

Miramar BrickSlip with BuffPointing Mortar

Miramar BrickSlip with BlackPointing Mortar

Miramar BrickSlip with BrownPointing Mortar

Miramar Brick Slip with Sandstone Pointing Mortar

Miramar Brick Slip with DarkGrey Pointing Mortar

Miramar Brick Slip with Natural Grey Pointing Mortar

Figure 1.21: Several type of colour mortar for pointing works.

The best way is to mix up a small amount beforeyou start the main job, measure the mixtureusing a small cup etc (use a bucket for normal

mix). A starting point would be 1 part Portlandcement to 4 parts Sand. The best idea would beto mix up

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several mixtures one at 1 to 3, 1 to 4, 1 to 5and 1 to 6 let them dry and see which is theclosest to your existing mortar.

There are many types of sand and each type willproduce a different colored mortar when mixedwith cement, if your mortar is very light ordark color take a sample of the loose mortar tothe local builders merchant, he may havesupplied the sand or be able to help you locatesome. Some mortars are artificially colored witha cement dye making it even harder to match.

CHOOSING A MORTAR COLORUsing a colored mortar can have a dramaticeffect on the appearance of brickwork.

The images in Figure 1.13 below illustrate theextent to which the color of the mortarcan change the appearance of brickwork. Thebricks on the left are exactly the same as thoseon the right - only the mortar color differs

The image below shows how dramatic patterns canbe created by using different mortar colors. The pattern you see in the photo below isactually created by the mortar, yet it gives theillusion that it has been created with differentcolored bricks. Around 15% of the area of awall is made up of mortar, so it's notsurprising that using different colored mortarscan have such an effect.

Different colored mortars are created usinga combination of colored sands and cements, orready mixed colored mortars.

It is well worth making a careful choice as toboth the color and style of the mortar joints asthey can truly enhance the effect of yourcarefully chosen bricks. Incorrect mortar choicewill have a detrimental effect on the appearanceof your brickwork, even if you have chosenexpensive handmade bricks. When matching the existing brickwork for anextension or renovation project, matching themortar and mortar joint is as important asmatching the brick.

COLORED POINTING MORTARSThe color of the pointing mortar you choose inaccordance with your brick/stone can make adramatic difference to the overall look and feelof a finished project as in Figure 1.20 and 1.21with some of the colors lending themselvesaesthetically better than others.

COMPO MORTARLime-cement mortar is also known as compositionor “compo” mortar, guarded or gauged mortar. Themix contains, lime, cement and sand inproportions depending on the requirements of thework. A satisfactory mix for most work is 1 part

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Hydrated Lime, 1 part Cement and 6 parts sand byvolume. For improved workability increase the lime andreduce the cement, a suitable mix being 1 partcement, 2 parts lime and 9 parts sand. Lime-cement mortar is most suitable because itcombines the advantages of good workability withearly strength. It should be used up within anhour of mixing, however, it is not suitable forworks below the damp course level.

Addition of lime to cement mortar makes themixture thicker and stickier while wet. Additionof cement to lime mortar acts as a pozzolangiving some degree of quick set, but this comesat a price, and is not recommended.

Three cement & lime mixes have been widely used.1. 1:1:6 is a satisfactory mortar mix for

various purposes, but behaves as cement basedmortar.

2. 1:2:9 has been found to be prone to prematurefailure, and is no longer recommended

3. 3:1 + 5% cement makes a lime mortar thatfirms up quickly, avoiding delays to work,but the addition of cement has been found tobe associated with premature failures, andthe practice is no longer recommended.

1:2:9 and 1:1:6 are frequently mistaken for limemortars, but are considered cement mortars, asalthough they contain substantial amounts of

lime, their properties are primarily those ofcement mortar. 1:1:4 (lime + O.P.C + sand) isthe usual mix for the experienced builder.

NOTE this calculation is based on weight NOTvolume.

MAKING MORTARIf you are starting a project you can decidewhat mixes to use see table below:

The general mix would be used in normalconditions the strong mix would be used forsevere conditions of wind or rain or if the siteis elevated or near the coast.

LIME AND PLASTICISERSThe lime is added to slow down the dryingprocess and to help the mixture flow, howevermany builders use a plasticizer instead of thelime this also improves workability of mortarand minimizes cracking and crazing, followmanufactures instructions on the amount to use.

TYPE OF MORTAR MIX CEMENT SAND LIME

GENERAL MIX 1 PART 6 PARTS 1 PART

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STRONG MIX 1 PART 4 PARTS 1/4 PARTTABLE 1.5: Mortar mixing formulas for bricklaying.

MIXINGMix together with water until you get butterlike consistency, slipping easily off the trowelbut still holding its shape if you make adepression. Don’t use the mix after 2 hours orless in very hot weather.

GROUTGrout is a cement mortar that is fluidic innature, and is used to fill the joints and voidsin masonry work, and to repair cracks. It isequally used to increase the bearing capacity ofsoil by injection. It is used to fill the cracksformed after the concrete sets and hardens indam construction.

Grout is different from mortar in its fluidityand it is poured and not spread with trowel aswith ordinary mortar. It is made up of cement,fine or coarse sand, water. Grouting admixturemay be added if desired. The water-cement ratioshould be low to increase the strength andreduce shrinkage.

TERMINILOGIES IN BRICKLAYINGFROG UP/DOWNA frog as shown in Figure 1.26 is a recessedpart of a surface of a brick. Pressed bricks arelaid ‘frog up’ when maximum strength is requiredespecially in engineering work. This method alsoincreases the mass of a wall and decreases soundtransmittance. Pressed bricks may be laid frogdown; this method is favored by the bricklayersince less mortar is required for bedding. Theremay also be a marginal increase in thermalinsulation due to the entrapped air pockets. Adisadvantage of this method is that with brickshaving a very deep ‘V’ shaped frog there may besome difficulty in making reliable fixings tothe wall when the fixing hits an air pocket.

WIRE CUT Bricks may be laid either way up but

some types of wire cuts have a textured (combed)face creating folds in the face of the brickwhich is directional. It is advisable to laythese bricks with the folds hanging downwards tomaximize the weathering characteristics of thebrick.

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TIES Ties or cavity ties are used to tie

layers of brickwork into one another, to form astructural whole. A common type is a figure-eight of twisted wire, generally stainless steelto avoid failure due to corrosion. The loop ateither end is buried in the mortar bed as thewall is built up.

MORTAR A mixture of sand, lime and Portland

cement, mixed with water to a workableconsistency. It is applied with a bricklayer'strowel, and sets solid in a few hours. There aremany different mixes and admixtures used to makemortars with different performancecharacteristics.

Figure 1.22.—Names of brick surfaces.

POSITIONThe six position as shown in Figure 1.18 are:1. Bond

A pattern in which brick is laid2. Stretcher

A brick laid horizontally, flat with thelong side of the brick exposed on the outerface of a wall.

3. HeaderA brick laid flat with the short end of thebrick exposed.

4. SoldierA brick lay vertically with the narrow("stretcher") side exposed.

5. SailorA brick lay vertically with the broad sideexposed.

6. RowlockA brick laid on the long, narrow side withthe small or "header" side exposed.

7. ShinerA brick lay on the long narrow side withthe broad side exposed.

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Figure 1.23: Six positions of bricks.

MASONRY TERMS To lay brick efficiently and effectively, youmust be familiar with the terms that identifythe position of masonry units in a wall. Thefollowing list, which is referenced to figure1.19, provides some of the basic terms you willencounter.

Masonry is defined as the art of construction inwhich building units, such as clay bricks, sand-lime, bricks, stones, Pre-cast hallow concreteblocks, concrete slabs, glass bricks,combination of some of these building units etcare arranged systematically and bonded togetherto form a homogeneous mass in such a manner thatthey can with stand point to other loads and

transmit then through the mass without fail ordisintegration.

Masonry can be classified into the following categories:1. Stone masonry2. Brick masonry3. Hallow block concrete masonry4. Reinforced masonry5. Composite masonry

These can be further sub-divided into varies types depending upon workmanship and type of materials used:

1. Solid brickwork The simplest type of wall is constructed insolid brickwork, normally at least one brickthick. Bricks are laid in rows known ascourses; the arrangement of headers andstretchers in each course gives rise todifferent patterns or bonds.

2. Cavity wallsIn a cavity wall, two layers (or leaves) ofbrickwork are tied together with metal ties,with a cavity or 2 to 4 inches that may befilled with insulation.

3. Brick facing

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http://en.wikipedia.org/wiki/File:Brickpositions.PNG


A non-structural outer facing of brick istied back to an internal structure: a layerof block work, timber or metal studwork etc.

Figure 1.24: Masonry units.

DEFINITIONS OF TERMS IN BRICKLAYINGCOURSE

A course is a horizontal layer of bricks stonesor one of several continuous, horizontal layers(or rows) of masonry units bonded together.

BEDThe surface of a stone perpendicular to the lineof pressure of (lower surface of bricks orstones in each course).

BACK The inner surface of wall not exposed is calledback. The material forming back is known asbackingFACE

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The exterior of the wall exposed to weather isknown as face. The material used in the facingof wall is known as facing’

HEADIt is a brick or stone, which lies with itsgreatest length at right angles to the face ofthe work. Head or also call header is a masonryunit laid flat on its bed across the widthof a wall with its face perpendicular tothe face of the wall. It is generallyused to bond two wythes.

WYTHEThe wythe is a continuous vertical section of awall, one masonry unit thick. This is sometimescalled a tier. Figure 1.10 —Masonry units. Thecentral wall that dividing two shafts and mostlyused to divide flues within a chimney.

STRETCHERIt is a brick or a stone which lies with itscongest side parallel to the face of the work ora masonry unit laid flat on its bed along thelength of a wall with its face parallel to theface of the wall.

BONDThe method of arranging bricks so that theindividual units are tied together

QUOINSThe stones used for the corners of walls ofstructure or a corner in masonry.

BATA cut brick. A quarter bat is one quarter thelength of a stretcher. A half bat is one half Itis a portion of a brick cut across the width.

CLOSERA cut brick used to change the bond at quoins.Commonly known as quarter bat. It is the portionof a brick cut in such a manner that its onelong face remains uncut

QUEEN CLOSERIt is the portion of a brick obtained by cuttinga brick length-wise into two portions or a brickwhich has been cut over its length and is astretcher long and a quarter bat deep. Commonlyused to bond one brick walls at right angledquoins.

KING CLOSERIt is the portion of brick obtained by cuttingoff the triangular piece between the centre ofone end and the centre of one side or a brickwhich has been cut diagonally over its length toshow a half bat at one end and nothing at theother.

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BEVELLED CLOSERIt is the portion of a brick in which the wholelength of the brick is bevelled for maintaininghalf width at one end and full width at theother

FROGIt is an indentation or depression on the topface of a brick made with the object of forminga key for the mortar.

COPINGIt is the course placed upon the exposed top ofan external wall to prevent the seepage of water

BULL STRETCHERA rowlock brick lay with its bed parallel to the face of the wall.

ROWLOCKA header laid on its face or edge across thewidth of a wall.

PARTY WALL A wall shared by two properties or parties

BULL HEADER A rowlock brick lay with its bed perpendicularto the face of the wall. SOLDIER

A brick lay on its end with its faceperpendicular to the face of the wall.

MOVEMENT JOINT A straight joint formed in a wall to containcompressible material, in order to preventcracking as the wall contracts or expands.

AIR BRICK A brick with perforations to allow the passageof air through a wall. Usually used to permitthe ventilation of under floor areas.

STOPPED ENDThe end of a wall which does not abut any othercomponent.

DOG TOOTH A course of headers where alternate bricksproject from the face.

SAW TOOTH A course of headers laid at a 45 degree angle tothe main face.

SLEEPER WALL A low wall whose function is to provide support,typically to floor joists.

HONEYCOMB WALL

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A wall, usually stretcher bond, in which thevertical joints are opened up to the size of aquarter bat to allow air to circulate. Commonlyused in sleeper walls.

SHEAR WALL A wall designed to give way in the event ofstructural failure in order to preserve theintegrity of the remaining building.

FIRE WALL A wall specifically constructed tocompartmentalize a building in order to preventfire spread.

INDENT A hole left in a wall in order to accommodate anadjoining wall at a future date. These are oftenleft to permit temporary access to the workarea.

BULLNOSERounded edges are useful for window sills, andcapping on low and freestanding walls.

TOOTHING The forming of a temporary stopped as in Figure1.25; end in such a way as to allow the bond tocontinue at a later date as the work proceeds.

1. The act or process of indenting or furnishingwith teeth.

2. (Masonry) Bricks alternately projecting at theend of a wall, in order that they may bebonded into a continuation of it when theremainder is carried up.

In leaving a section of brickwork so thatsubsequent work can be bonded into it, the endis finished in what is known as "toothing."Toothing is a vertical break in the wall butwith alternate courses left projecting asufficient distance to assure good bond with theportion to be afterward built, this end thuspresenting a toothlike appearance.

Toothing should be avoided wherever possible; itis difficult to construct the new portion sothat the whole wall, including the old and newportions, will act as a unit in resistinglongitudinal stresses. There is generally a;weak point at the toothing. It is very seldomthat the joint at which the too thing comes isnot evident. Strap iron can be used to help insecuring a better bond as described under"Blocking."

FILLING TOOTHINGSThe best way to fill toothing is to cut thebrick to a wedge shape by slightly trimming theupper and lower surfaces so that the face of thestretcher is left unimpaired, the narrowest

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point of the wedge being the back corner of thebrick at the end to be driven home.

The hole should first be wet and plastered withmortar on all sides. Enough mortar should beplaced in the hole to ooze out about the jointwhen the brick is driven into place. A quickerjob may be made by not cutting the brick and bybuttering the joint. This is not considered suchgood practice as it is hard completely to fillthe joint with mortar.

RACKING BACKStepping back the bond as the wall increases inheight in order to allow the work to proceed ata future date as in Figure 1.26 and 1.27..

The stepping back of courses of brick as inFigure 1.28 during the construction phase of awall, usually in expectation of the wall’scompletion at a later date.

Figure1. 25: Elevation of toothing

Figure 1.26: An elevation of racking

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In raising a corner, the courses end in a seriesof steps in order that the men on the wall maytic their courses to it in the easiest manner.In other words, each course on the wall will beshorter than the course below it.

BRICK USAGEThere are three main categories of use, and bothpressed bricks or wire cut brick types are usedin all three categories.

FACING BRICKWORK Facing brick is the visible decorative work.

ENGINEERING BRICKWORKEngineering brick often seen in bridges andlarge industrial construction but may also behidden in ground works where maximum durabilityis required e.g. manhole construction.

COMMON BRICKWORKCommon brick is not usually seen and is usedwhere engineering qualities are not required;below ground in domestic buildings and internalwalls for instance.

BRICK BOND

Bricks may be laid in a variety of 'bonds' orpatterns of headers and stretchers on a seriesof courses. In single-thickness walls, these arepurely decorative, but in double-thicknesswalls, they strengthen the wall by connectingthe layers

Figure 1.27: Isometric view of racking back

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Figure 1.28: Isometric view of racking back at corner.

PRINCIPLES IN BRICK BONDING1. Avoid continuously the vertical joint.2. Arrangement must overlap with each other.3. Vertical wall with continuous joints will be

less strong and unstable.4. Closers should never be built into the face

of the wall except next to a quoin header.5. All the joints should be flushed up with

mortar on every course.6. In every change of direction on the same

course, the bond should change.7. Ensure the stability of wall being built, to

control art design and surface of brick.

8. The tie bricks at junctions or quoins shouldbe well bonded to secure the walls together.

9. The perpends or cross joints in alternatecourses should be kept vertical.

10. A three-quarter bat starting a stretcherbond.

11. A closer next to the quoin header.

STACK BONDA pattern made up of rows of stretchers witheach stretcher centered on the stretcher belowit. All joints run vertically down the entirewall as in Figure 1.29.

STRETCHER BONDStretcher bond is one of the most common bonds. It is easy to lay with little waste and composedentirely of stretchers set in rows, offset byhalf a brick.

Stretcher bond is the commonest bond used todayand the least interesting in appearance. It canbe made more interesting by laying a course ofdifferent colored bricks or to lay such bricksto form a pattern on a wall.

PLAN FIRST LAYER

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SECOND LAYER PLAN

ELEVATION

Figure 1.29: Plan and elevation of stack bond

PLAN FIRST LAYER

PLAN SECOND LAYER

ELEVATION

Figure 1.30: Plan and elevation of stretcherbondWalls built using the traditional Stretcher bondare just a half brick wide. As with any wallbuilt of brick, no two adjacent vertical jointsshould be in line.

With a straight wall this is not a problem, justoffset each course by half a brick.

When turning a corner at the end of a straightrun again causes no problems, just interlock thetwo runs of bricks on every other course.

Stretcher bond, also known as running bond,consists of bricks laid with only their longnarrow sides (their stretchers) showing,overlapping midway with the courses of bricksbelow and above as shown in Figure 1.30.

It is the simplest repeating pattern as inFigure 1.31, but since it cannot be made with abond to the bricks behind it is suitable onlyfor a wall one half brick thick, the thinnestpossible wall. Such a thin wall is not stableenough to stand alone, and must be tied to asupporting structure.

It is common in modern buildings, particularlyas the outer face of a cavity wall, or as thefacing to a timber or steel framed structure.

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Stretcher bond is now used in building gardenand boundary walls which are "stand alone" byincorporating a layer of steel brick reinforcingmesh, laid every three or so courses thus actingas headers in tying the two leaves together.

When joining into a wall part way along thewall, it's necessary to use two 3/4 bats(colored red - one on either side) on the mainface of the wall on every other course.

Figure 1.31: Stretcher in isometric view.

Figure 1.32: Header bond in building façade makethe building bigger.

FIRST LAYER PLAN

x x

x x

SECOND LAYER PLAN

x x

x x

x x

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x x

ELEVATION

Figure 1.33: Header bond first layer plan, second layer plan and an elevation with ¾ brick shown as X.

HEADER BONDA brickwork bond composed entirely ofoverlapping headers as shown in Figure 1.32 and1.33.

FIRST LAYER PLAN

SECOND LAYER PLAN

ELEVATION

Figure 1.34: English bond layout plan andelevation with queen closer shown as X.

This bond is also known as Spanish bond, was avery common bond for bearing walls. It iscomposed of header bricks, set in rows that areoffset, ¾ inch of a brick as a quoin brick inalternating courses, which produces a solid easyto lay bond.Header bond is created by rows of headers, onlydisplaced by half a brick on each row. This bondis often using to create curved brickwork.

Header bond was sometimes used to help make abuilding look bigger. Civic buildings and theodd town-house can be found in Header bond. It's also used where there is a lot ofornamental detail, presumably to avoid a lot ofunsightly and costly cutting.

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ENGLISH BONDEnglish bond consists of alternating courses ofheaders and stretchers, with the alternativeheaders centered over and under the verticaljoints of the stretchers.

This bond has two alternating courses ofstretchers and headers, with the headerscantered on the stretchers, and each alternaterow vertically aligned. There is a variant inwhich the second course of stretchers is halfoffset from the first, giving rise to Englishcross bond or Dutch bond.

English bond is easy to recognize because itconsists of a course of headers followed by acourse of stretchers as in Figure 1.29. Althoughthe bond was very common in the Victorian periodit was not generally used for houses, but wasused in factories, stations and retaining wallsetc. It's a very strong bond but probably not asattractive as Flemish bond. English bond is madeup of alternating courses of stretchers andheaders. This produces a solid wall that is afull brick in depth.

English bond is easy to lie and is the strongestbond for a one-brick-thick wall. English bond is always likely to be the bondfound in the walls of bridges and viaducts. The

bond may be several bricks thick and the bricksthemselves are likely to be strong engineeringbricks

FIRST LAYER PLAN

SECOND LAYER PLAN

x x

x x

x x

x x

ELEVATION

Figure 1.35: Flemish bond layout plan andelevation with queen closer shown as X.

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FLEMISH BONDFlemish bond consists of alternating headers andstretchers along each course with the headerscentered on the stretchers above and below asshown in Figure 1.35.

Flemish bond, also known as Dutch bond, hashistorically always been considered the mostdecorative bond, and for this reason was usedextensively for dwellings until the adoption ofthe cavity wall. It is created by alternatelylaying headers and stretchers in a singlecourse.

The next course is laid so that a header lies inthe middle of the stretcher in the course below.This bond is two bricks thick. It is quitedifficult to lay Flemish bond properly, sincefor best effect all the perpendiculars (verticalmortar joints) need to be vertically aligned. Ifonly one face of a Flemish bond wall is exposed,one third of the bricks is not visible, andhence may be of low visual quality. This is abetter ratio than for English bond, Flemishbond's main rival for load-bearing walls.

MORTAR JOINTING AND POINTINGBrickwork can either be pointed or jointed. Mostbrickwork, these days, is jointed as workproceeds. Pointing is the term used to describeexisting or new joints which have been raked outand filled with fresh, often colored, mortar.Pointing is relatively rare in new constructionbecause colored mortar mixes are now relativelycheap. In addition pointing requires great care.The pointing mortar mix must be slightly weakerthan the jointing mortar. If it is stronger theouter face of the bricks, immediately above andbelow the pointing, will carry excess load. Thiscan result in the edges of the bricks spalling.

POINTINGPointing is act of filling the joints 15 mm to20 mm from outer surface with rich mortar (1:2ratio of cement and sand). This is done toobtain various objectives from detailed workwhich may look beautiful to make economic use ofmortar where there are not enough resources toplaster and so on.

Types of Pointing are, Flush, Struck, V,Grooved, Weather, Recessed Pointing and Tuckpointing.

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JOINTINGJointing is act of layering the constructionalmaterial (Stone, Brick or Concrete Block) andalso making the Joints in Concrete slabs.

DIFFERENCES1. Jointing comes first because “pointing is

enhancement of joints.

2. Jointing is done to bind(adhere/stick/strengthen) the constructionalmaterial where pointing is done to make thebonds look beautiful and become resistantagainst weather effects and dampness

3. Jointing is considered basic and intrinsic toconstructional work (Also called Masonry ifit is done with Bricks/Stones/Blocks), wherepointing is additional favor to the building.

4. Jointing deals with how building materialsare to be placed with each other and how canthey strengthen each other and is aided bythe mortar, hence 'Jointing' needs (1)Building Material (2) Mortar; Pointing dealswith how to 'ENHANCE' the JOINT by using moreMORTAR, hence it needs 'MORTAR'.

Pointing is the term used to describe existingor new joints which have been raked out and

filled with fresh, often colored, mortar.Pointing is relatively rare in new constructionbecause colored mortar mixes are now relativelycheap. In addition pointing requires great care.The pointing mortar mix must be slightly weakerthan the jointing mortar. If it is stronger theouter face of the bricks, immediately above andbelow the pointing, will carry excess load. Thiscan result in the edges of the bricks spalling.Pointing is applying a small amount of mortarinto the face joint between bricks (either newlylaid or in old brickwork). In new brickwork,pointing can apply harder mortar to increaseweather protection on exposed faces. In oldbrickwork, pointing is often used to repairmortar joints which have been eroded by exposureto the elements

MORTAR FOR POINTING:The pointing is generally adopted for thefinishing of exposed external walls of astructure. It is cheap in the first coat, but itrequires frequent replacement.

The pointing may be carried out either in limemortar or in cement mortar.

1. Lime Mortar: 1:2 mix (1 lime :2 sand orsurkhi)These two materials are carefully ground in amortar mill. The sand to be used for

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preparing lime mortar should be clean fineand free from any organic impurities

2. Cement mortar: 1:3 mix (1 cement : 3 sand)The cement should be comply with standardrequirements and sand should be clean., fineand free from ay organic impurities. Thematerials are thoroughly mixed in drycondition before water is added to them. Themixing of the materials is done on awatertight platform and mortar of one cementbag only is prepared at a time and thisquality of mortar is consumed within 30minutes after adding water.

The pointing can be carried out in a numberof shapes. The choice of a particular typewill depend on the nature of masonry and theeffect required

JOINT AND POINTING SHAPESThe best joint is one with a concave shape; somecall it a bucket shape - a slight, indented,rounded surface starting at the edge of thebordering brick and meeting the next. This jointallows water to run over it easily, with noplace for water to stop.

There are various styles of jointing/pointingalthough as shown in Figure 1.36 and 1.37,

nowadays, economics rather than aesthetics tendto dictate the style specified.

The bucket handle joint may not be the mostattractive but, done correctly, will play itspart in enhancing the life of the wall. This isbecause the bucket handle is a tooled joint -tooling the mortar helps seal the joint, andcompresses the mortar slightly, improving itsresistance to water penetration.

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Figure 1.36: Sectional view of jointing

CONCAVEA concave joint is "U" shaped and is made usinga convex-shaped slicker like in Figure 1.36.

In this type mortar is first up flush with theface if wall. A semi circular notch is formed bya tool know as pointer. This type of pointinggives as attractive appearance to the surface.This type is mostly used for superior type work,particularly for vertical joints of walls.

V SHAPENamed for its concave, "v" look, the v-joint isformed with a brick jointer called a v-jointslicker as in Figure 1.36. In its website, thetool company bon states that this is aneffective joint for moisture resistance, alongwith concave and weathered joints.

WEATHERED JOINTThe weathered joint is one of the most timesconsuming to make, as it must be worked frombelow like in Figure 1.37 and 1.39. Theweathered joint is angled from the top with atuck pointing trowel, creating something thatlooks like a slash mark (/), with the depth ofthe mortar increasing toward the upper brick.

If weathered pointing is used, there is slopingoutward from the upper brick to the one below.From its name it is suitable for all walls,especially those exposed to harsh weatherconditions.

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Fill and shape the vertical joints first, thenuse the edge of the trowel to press in the upperedges. Use the trowel along the edge of theboard to cut the lower edge straight.

A strip of metal bent at the end is suitable fora smooth finish. There is also a tool availablefor this job called a Frenchman. This looks likea knife with the tip bent over at 90°. When themortar is almost dry, lightly brush it

Figure 1.37: Jointing finishes for mortar

Figure 1.38: Concave jointing

across its top to brush away any odd scraps of mortar - but keeping the brushing light enough to avoid damage to the pointing.

FLUSH POINTINGCut off excess mortar with a brick trowel tocreate a flush joint as in Figure 1.37 and 1.40.This will create a smooth joint that is the samedepth as the bricks. Family Handyman recommendsthis joint for repointing brick sills, ledges,and other horizontal structures in order toimprove and promote drainage.

Flush pointing the pointing may be level as inflush pointing, which is made by wiping over thefinished pointing with the trowel or piece ofrough cloth. It is a suitable finish forsections of wall containing second-hand bricks,

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which have lost the sharper edging required fora different style of pointing.

STRUCK JOINTThe struck joint is the opposite of theweathered joint, looking like a backslash (\)between two bricks, although both are made witha trowel. "a treatise on architecture andbuilding construction" advises that all outsidebrickwork have struck joints, which does notallow water to settle in the joint and steepinto the mortar as in Figure 1.36 and 1.42.

RAKED JOINTStruck pointing gives a splayed finish. It's anattractive joint but skill is required to keepthe angle constant. It's a slower and moreexpensive operation than a bucket handlejoint. The picture on the right shows a parapetwall (built about 1900). This wall has been laidin a cheap mortar and then pointed at a laterdate

Figure 1.39: Weathered joint

Figure 1.40: Flush pointing

Figure 1.41: Raked joint.

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in a better quality mortar. You can see thatsome of the pointing mortar has come away fromthe brickwork.

A raked joint is made with a raking block, whichthe family handyman website makes by hammering a6d box nail into a small 1-inch x 2-inch boardso that it is the same depth as the old joints.Take the raking block and use it to remove themortar until it is 1/4 inch below the brick likein Figure 1.41.

RECESSED POINTRecessed joints are not suitable for buildingsin exposed situations because they do notreadily shed water. Only bricks with good frostresistance should be used with recessed joints.A depth gauge (left) helps keep the recessedjoint constant.

BEADED JOINTAs its name implies, the beaded joint is convexand creates a "bead" of mortar that protrudesbeyond the brick as in Figure 1.42. "Simplestonescaping" states, "beaded joints, typicallyseen on granite walls and foundations ofcraftsman-era houses, form a protective barrieragainst weather deterioration and saturation onthe joints that hold the stone. They are shapedwith a tool called a beader"

GRAPEVINE JOINTThis decorative joint is formed with a grapevineslicker that has a central rib. The joint isflat, but has what online tips calls a "deep u-shaped shadow line in the center"

EXTRUDED JOINTAn extruded or "squeezed" joint is madenaturally from excess mortar that is squeezedout from between two bricks shown in Figure1.42.

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Figure 1.42: Jointing and pointing that includedextruded and beaded.

BRICKS IN BUILDING CONSTRUCTIONREINFORCE BRICKWORKReinforced brick work is joints in brick-workthat give an extra strength, usually by metalbars, mesh, rods, or wires across the joints.Reinforced masonry is popular as well forengineered masonry construction.

Methods of reinforcing the most common methodsused to reinforce brickwork include1. Wire reinforcing 2. Steel rod reinforcing 3. Special brick bonding arrangements 4. Pocket reinforced brickwork

WIRE REINFORCING:The use of masonry reinforcement is a verysimple and cost-effective way of greatlyenhancing the strength and durability of brickconstruction. It provides both structural andcrack control benefits.

Wire reinforcement benefits include: 1. Bonds and strengthens corners and wall

intersections. 2. Resists cracking in areas of uneven

settlement. 3. Bonds walls to reinforced concrete frames. 4. Easy folding for corners, curves and angles. 5. Safe to handle and easy to cut and shape on

site.

The most common types of wire reinforcinginclude…….. 1. Brickforce 2. Bricktie3. Bricktore or mesh 4. Wallforce

BRICKFORCE Brick Force masonry reinforcement is specifiedinto projects by consulting engineers for itscost and time saving properties.Brick Force consists of two parallel wiresjoined by cross wires. The flattened profile ofthe main wires allows for efficient lapping andensures sufficient mortar cover to develop bondas in Figure 1.43.

Brick Force is available in both galvanized andstainless steel material.

BRICKTIE 57


Brick tie 1. Available in widths to suit any required wall

make up. 2. The most common form is 175mm wide to suit a

215mm collar-jointed wall constructed fromtwo leaves of 100mm.

3. By tying the two leaves together, the wallmay be designed as if it were solidconstruction.

Bricktie is designed for use when constructing acollar jointed wall from two thinner blocks.Bricktie eliminates the need to lift heavyblocks by providing the necessary ties for thewall to be designed as a single leaf.

A 215mm thick wall can be easily constructedusing two 100mm blocks with a 15mm collar joint.Brick tie is available in both galvanized andstainless steel material.

Bricktie was developed to overcome the problemsassociated with lifting heavy blocks in theconstruction of 215mm and greater thicknesswalls. By tying the two masonry leaves together,the wall may be designed as if it were solidconstruction. The use of bricktie also enables afair-faced block finish to both sides of thewall by adopting a collar-joint construction.

Figure 1.43: Brickforce from top left placementin wall construction, top right and below twocommon type of brickforce

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Figure 1.44: Bricktielaid on mortar duringbricklaying.

Figure 1.45: Close-up look of bricktie.

Figure 1.46: Layingbricktie on mortar

Figure 1.47: Bricktie on block.

Similarly, a single solid brick wall can beconstructed using stretcher bond coursingwithout the need for any additional ties.Bricktie as in Figure 1.43 provides an effectiveand time saving solution to most wallcombinations and consists of a 20 x 3mm flat tie

welded to two longitudinal flattened reinforcingwires. Bricktie like in Figure 1.45 is availablein widths to suit any required wall make up,although the most common form is 175mm wideBricktie to suit a 215mm collar-jointed wallconstructed from two leaves of 100mm. Inaddition, the longitudinal wires can be utilisedfor either structural strength or to extend thedistances between movement joints as in Figure1.46 and 1.47.

BRICKTOR OR MESH Bricktor or mesh is manufactured from hightensile woven wire available in stainless steeland galvanised finishes. It lies flat on themortar bed joint making the product easy toinstall compared to other coiled products as inFigure 1.34 and 1.35. Brick Wall ReinforcementMesh also know as Brickwork ReinforcementMesh is used primarily as anti-crackingreinforcement in the construction of brick andblock masonry. Wire mesh series include expandedmetal coil mesh for brickwork reinforcement inall types of buildings such as reinforcement ofroad, tunnel reinforcement, ground paving,swimming pools, concrete reinforcement and floorreinforcement.

Features of Coil Mesh:1. Economic transport

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2. Ease and economy of storage space3. Reduction of implementation time (high

application performance)4. Installation does not require skilled labor5. Quality ensured by the implementation in

factory6. Reduction of waste and failings.

Description of truss wire meshes reinforcement:1. 16″ O.C. Truss design positions cross rods on

web of block to allow core clearance.2. Simplifies rebar installation; centering

utilizes strength of grout.

Figure 1.48: Coil wire mesh

Figure 1.49: Truss wire mesh reinforcement

3. Allows unrestricted flow of grout or loosefill insulation into CMU cells.

4. Minimizes re-setting of joint reinforcementaround rebar.

5. Improves resistance to shrinkage cracking.6. Provides stronger bond with cross rods in web

of block.7. Less time devoted to rebar installation,

grout pouring.8. Meets ASCE/ACI 530 building code requirements

for masonry structures and ASTM A 951(standard specification for masonry jointreinforcing).

9. Minimizes re-setting of joint reinforcementaround rebar.

10. Improves resistance to shrinkage cracking.11. Provides stronger bond with cross rods in

web of block.

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http://wirebond.com/wp-content/uploads/2009/06/3002w1.jpg

http://wirebond.com/wp-content/uploads/2009/06/3002ws1.jpg


12. Less time devoted to rebar installation,grout pouring.

13. Meets ASCE/ACI 530 building coderequirements for masonry structures and ASTMA 951 (standard specification for masonryjoint reinforcing).

14. Available finishes in mill galvanized, hotdip galvanized and stainless steel like inFigure 1.48 and 1.49.

WALL FORCE Wallforce combines the benefits of reinforcing both leaves of a cavity wall with welded integral cavity wall ties.

Consists of four flattened profile main parallelwires with cavity wall ties welded across its width as show in Figure 1.50.

Wallforce has been designed for use in double-leaf collar joint walls, and can reduce theproblems on site with heavy blocks, using 2 x100mm blocks tied together with Tiespan type 1to replace a 215mm block. This method ofconstruction also gives the wall a 6 hour firerating. Tiespan type 1 is manufactured fromstainless or galvanised steel with 4mm or 3.5mmmain longitudinal wires with 20mm flat crossties. Each length is 2700mm long x 175mm wide.

STEEL ROD REINFORCING

When added strength is needed, brick walls,columns, beams, and foundations are reinforcedin the same way as in concrete construction. 1. In this type of reinforcing, steel rods are

placed within a cavity like in Figure 1.512. The cavity is then filled with either mortar

or a concrete grout. 3. This binds the rods to the brickwork giving

lateral strength to the wall

SPACINGThe minimum spacing between steel reinforcingbars should be 1 1/2 times the diameter of thebar itself. When you lay reinforced bricks, thethickness of the mortar joint should be 1/8 inchmore than the diameter of the steel bar itself.This allows for 1/16 inch of mortar between thesurface of the brick and the reinforcing bar.

BARS Reinforcing steel can be placed in bothhorizontal and vertical mortar joints. 1. Horizontal Bars.

Lay horizontal bars in the bed of mortar, andthen pushes them down into position. Spreadthe mortar on top of the bar, and smooth ituntil you have a bed joint of the properthickness.

2. Vertical Bars. Place vertical bars in the vertical joints.Hold them in position by wood templates at

61


the proper bar spacing, or wire them to thehorizontal bars. Then lay brick up around thevertical bars.

Figure 1.50: Wall force in action.

Figure 1.51: Reinforced brick-beam construction

3. Stirrups.

Z-shaped steel reinforced bars, calledstirrups, are shaped to fit the mortarjoints. Place the lower leg of the stirrupunder the horizontal bars. You may need tomake the mortar joint thicker at this point(Figure 1.36).

REINFORCING STEELSteel bars are used asreinforcement in thecase of reinforcedmasonry (Figure 1.50 and1.51).

According to EC 6,reinforcing steel may beassumed to possessadequate elongationductility, if thefollowing requirementsare satisfied:1. for high ductility

class2. for normal ductility class

In the case where high bond rebar with diameterless than 6mm is used it should not beconsidered as having high ductility. Whenprefabricated ladder-type or truss-type bedjoint reinforcement is used it should beconsidered as having normal ductility.

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SPECIAL BRICKS BONDINGSpecial brick bonding arrangements although nota common method of construction due to theirawkwardness & duration to build, the two brickbonding arrangements best suited to reinforcingbrickwork are: 1. Quetta bond 2. Rat trap bond

Steel rods are inserted within the pockets ofthese walls and the pockets are then filled withmortar or concrete which surrounds the steelgiving a bond between the steel and the brick.

A one-and-a-half brick wall (340mm thick) laidin Flemish bond like in Figure 1.53 has smallcontinuous vertical spaces in the centralthickness, normally filled with cut bricks.These can be used as cores into which verticalbars can be inserted, and grouted in afterseveral courses have been laid. This detail hasbeen

Figure 1.52: Quetta bond

Figure 1.53: Lay out plan of perforated bricks

used for heavy work such as air-raid sheltersand blastwalls, but walls of this thickness are seldomused in normal construction.

Bricks with purpose-made core holes are the mostpractical solution for accommodating verticalreinforcement. The core holes must be located inthe bricks so that they will align in normalstretcher bond. They have to be large enough toallow some tolerance in laying, and also largeenough to allow bars of the required diameter to

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be inserted, lapped where necessary, and groutedwith mortar or fine-aggregate concrete.

It is unreliable to insert a storey-heightreinforcing bar down the holes after the wall islaid, because any mortar droppings in the holeswill be impossible to remove. It is alsoimpossible to put storey-height bars in placefirst and thread the bricks over them.

Therefore the use of this system for laid-in-place walls requires some pre-planning anddiscussion with the bricklayers involved. It ismore easily adapted to prefabricated wall panelsin which the bricks are laid out dry on ahorizontal table and the joints are then filledwith grout as in Figure 1.52 and 1.53..On the other hand, if the weather resistanceprovided by a cavity wall is not an issue, thecavity itself could be reinforced and filledwith a fine concrete grout. It is stillnecessary to use cavity ties to hold the leavestogether, and to fill the cavity in reasonablysmall lifts to avoid excessive hydrostaticpressure from the wet concrete

POCKET REINFORCED BRICKWORK This reinforcement is contained in the rear of thewall. Pockets are left at the back of the brickworkto allow vertical sections of concrete to be poured

around steel. This type of reinforcing is normallyused in retaining walls

A construction system where steel reinforcementis embedded in the mortar joints of masonry orplaced in holes and after filled with concreteor grout is called Reinforced masonry. There arevarious practices and techniques to achievereinforced masonry. According to the ways inwhich reinforcement is arranged, reinforcedmasonry can be classified into three types:

1. Reinforced hollow unit masonry2. Reinforced grouted cavity masonry3. Reinforced pocket type walls

REINFORCED HOLLOW UNIT MASONRYThe most common type is the reinforced hollowunit masonry. Units from group 2a and 2b areused for this purpose. This construction type isdiscussed in the Concrete block reinforcedmasonry section.

REINFORCED GROUTED CAVITY MASONRYThe second type of reinforced masonry walls- thereinforced grouted cavity masonry is therecognized earthquake resistant type of masonry.It consists of a cavity masonry wall constructedfrom group 1 masonry units. Into the cavity isplaced a steel mesh providing the vertical andhorizontal rebar. In order to achieve integrityof the wall the two leaves are connected by

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means of standard wall ties or rebar. The sizeand number of connecting ties are determinedaccording to design calculations. However atleast 4 to 6 rebar links or an equivalent wallties per m2 of wall area should be provided.After completion of the reinforcement detailsthe cavity is grouted or in filled withconcrete.

The leaves are usually one masonry unitthickness (about 100 mm) and the size of thecavity is 60 to 100 mm wide. The concreting ofthe cavity can be done in steps afterconstruction of each course or in one operationafter the masonry walls in the whole storey havebeen laid. Before grouting the cavity, allmortar droppings on foundations or rebar shouldbe removed from the previous grout stop toensure proper bonding. To achieve satisfactorygrouting vent holes should be formed in the wallto allow for the air to escape and facilitateremoving away mortar debris at the bottom ofeach grout stop. The vent holes are formed aswork proceeds and these can be in the form ofopen mortar joints or masonry units left out.

Reinforced grouted cavity masonry wallconstruction is shown on Figure 1.54.

REINFORCED POCKET TYPE WALLThe third type of reinforced masonry walls-thereinforced pocket type walls is common for

engineered structural masonry construction.Vertical wall reinforcement can be placed invertical ducts( pockets) formed between solid orhollow masonry units. This is the case when socalled "quetta bond"( a brick and a half wallthickness bond) is constructed. In "quetta bond"close spacing of vertical rebar is possible. Thereinforced pocket type masonry also allows forforming reinforced masonry columns, where ductsof bigger size can accommodate multiple bars aswell as stirrups for concrete infill or groutconfinement.

For this type of reinforced masonry the verticalrebars are placed into position ideally beforethe laying of masonry units. Horizontalreinforcement is placed in the bed joints atvertical spacing maximum 600 mm. The verticalreinforced ducts are filled with concrete orgrout as the costruction of the wall progresses.Proper planning is necessary to ensure rebarsplices lengths, anchoring lengths, correctcover and keeping the concrete infill or groutsurface of each grout stop clean

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Figure 1.54: Reinforced grouted cavity masonryconstruction

Figure1.55: Reinforced pocket cavity masonryconstruction

from mortar debris. Reinforced pocket cavitymasonry wall construction is shown on Figure1.55.

In order to achieve durability of the reinforcedwall it is essential to ensure rebar protectionagainst corrosion or fire damage. For thispurpose is required that the reinforcement hassufficient concrete/grout cover. For unprotectedsteel in dry, humid or aggressive environmentthe cover should be respectively 20, 25 and 40mm thick.

Limitation of the size of horizontal rebar isrequired to achieve good embedment in themortar. It is recommended that rebar diameter ismax 6 mm when placed in standard 10 mm bedjoint.

The effectiveness of the reinforcement howeverstrongly depends on the type and quality of themasonry i.e. Masonry units and mortar. Whensubject to seismic load the bond between therebar and mortar deteriorates. Consequently hightensile stresses and yielding in rebar cannot bedeveloping preventing ductile behavior andenergy dissipation. For certain hollow masonryunits premature crushing of face shells undercyclic lateral load may occur even in caseswhere the compressive strength of the units isgood.

In order to achieve a ductile behavior ofmasonry is necessary that the shear strength ofthe wall is greater than the bending strength toensure bending failure. Therefore increased

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amount of vertical reinforcement at the edges ofwall may not improve the resistance of the wallparticularly with weak masonry units. Thus theminimum percentage of reinforcement, eithervertical or horizontal, depends on the strengthof the masonry units.

The maximum percentage of reinforcement shouldalso be limited based on the strength of themasonry units and mortar such that a ductilebending failure is possible. The requirementsfor anchoring and lapping of reinforcement aresimilar to those specified for reinforcedconcrete structures.

All reinforcement should be anchored to allowfor the stresses in the bar to develop. On wayto achieve economic anchorage is to terminatethe rebar past the point where it is no longerrequired. This is called straight anchorage asin Figure 1.63. According to EC 8 straightanchorage is not allowed for rebar with diametermore than 8 mm.

THE STRUCTURAL REINFORCEMENTFor structural reinforced masonry applicationsthe main wires are manufactured to a flattenedprofile to enable the product to be easilylocated into the mortar joint without steelbuild-up problems at lap positions

corners/junctions, or when used in conjunctionwith wall ties.

Structural reinforced masonry is available in arange of different main wire diameters forspecific structural loading situations, and in avariety of product widths to suit differentblock or brick leaf construction. To comply withquality assurance requirements and assist inproduct traceability, each strip of is uniquelymarked at regular intervals with the brand name,reference and manufacturing code.

BRICK CLADDING SYSTEMBrick cladding is an exterior facing for astructure which is made from brick. Whilecladding typically does not bear weight, thusnot contributing to the stability of astructure, it plays a number of important otherroles in a building. Examples of brick claddingcan be found all over the world, and brick isalso a very ancient building material which hasbeen used by many human cultures. For safetyreasons, brick cladding is sometimes notrecommended in seismically active areas, wherebricks could collapse during an earthquake,causing injuries or property damage.

1. Bricks can be run in a variety of patterns orcourses to create visual interest, and

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sometimes different types of courses are usedon the same structure for the purpose oftexturing and layering the building to makeit more aesthetically pleasing. The brickcladding can also feature multicolored brickand brick of different sizes for even morevariation.

2. This type of brickwork can be used to edgepaving and patios, along with windows anddoors in structures with brick cladding. Asoldier course may also be used as adecorative accent on a sidewalk or similartype of paving, or as an edging for gravelwalks.

FUNCTION OF BRICK CLADDING1. Cladding essentially comprises the external

envelope of a building, the layer of astructure which protects the inside.

2. Brick cladding is designed to shed and repelwater so that the water cannot reach theinternal framing of the building. Thisreduces the risk of damage to the framingcaused by mould and mildew.

3. It also keeps water out of the inside of thestructure, keeping the interior dry andpleasant.

4. Another function of cladding is to absorbsome impacts, and to provide some insulation.The multiple layers of a building aredesigned in part to trap air, creating aninsulating barrier which keeps temperaturesstable. The more layers of insulation, theless climate control is needed, because theclimate control is built into the structure.Impacts such as high winds and collisionswith object can also be absorbed in part bythe cladding, protecting the structuralelements of a building

5. Brick cladding also plays an aesthetic role.It's the part of the building which peoplesee, and therefore can shape how peopleperceive the building. Bricks can be run in avariety of patterns or courses to createvisual interest, and sometimes differenttypes of courses are used on the samestructure for the purpose of texturing andlayering the building to make it moreaesthetically pleasing. The brick claddingcan also feature multicolored brick and brickof different sizes for even more variation asin Figure 1.56.

Brick cladding is traditionally installed by amason, who may work with a team for reasons ofspeed. Some companies make false brick claddingwhich can be attached by general contractors.This type of cladding is less expensive than

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true brick, and is suitable for use in areaswhere brick construction may not be recommended.It can vary in quality from very believablefacsimiles of brick to cladding which may appearslightly off to the observer.

ADVANTAGES OF BRICK CLADDINGSYSTEM

VERSATILITYThe adaptability and sheer simplicity of ourbrick cladding systems set them apart from therest. Single runs of pre-bonded masonry panelsquickly slot into one another. These are securedwith screws into the timber or steel studs, ordirectly into the existing masonry as in Figure1.57. Different bonding effects can be used,e.g. Flemish bond, English garden wall bond.Feature brickwork can also be incorporated, e.g.lintels, corbels and arches. Special bricks suchas Dogtooth and plinth detail can also beincluded in your project with relative ease.

MATCHING Brick Cladding is ideal for dovetailing withexisting masonry. Using the same fasciamaterial, even the same type of mortar; enable

new developments to look like they have alwaysbeen there like in Figure 1.45.

QUAITY The panels are made from high density and rot-proof, industrial cement based board shown inFigure 1.5. Our Brick Cladding systems even havethermal and acoustic insulation properties. Asthey are prepared in a quality controlledfactory environment, fewer problems areexperienced on site, increasing the ease andspeed of installation.

SYSTEM ADVANTAGES1. Factory finished - Resulting in minimum site

wastage 2. Can be installed on - Wood, steel stud or

masonry sub-frame Suitable for walls up to30m in height

3. Durability - Guaranteed for 50 years 4. Variety of surface finishes - e.g. brick,

stone, marble, terrazzo and ceramics .5. Simple Fixing - Labor saving, No on-site

gluing Only a cordless drill needed 6. Lightweight - Approx. 40kg/m2 and 32 mm thick

(standard). Ideal for brick detailing of NonStructural facades i.e. Dormers and NonStructural gable details.

7. Easily Cut - Angle grinder (diamond tipped)Tile cutter Masonry saw

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8. Wide range of accessories - e.g. lintels,cills, corners, quoins, corbels, plinths &Dogtooth.

9. Also ideal for internal use - e.g. publichouses, retail outlets and domestic use

Figure 1.56: Brick cladding being used as façadeand finishes

BRICK CLADDING SYSTEMBrick Cladding System are the original and bestfor brick slips and stone faced claddingproviding a fast, cost effective way to get thereal look, feel and durability of brick andstone walling. The cladding has the added

benefit of thermal insulation, and also helps tosave energy, providing a greener alternative totraditional brick and stonework.

Although traditional bricks look great and feelgreat, when they are used as a veneer to providea weatherproof skin for the outer wall of abuilding, they offer no real structuralstability. They are also heavy, expensive andimpractical for use in modern constructionmethods. However, the brick slips and stonefaced cladding systems are lightweight and veryeasy to install, saving you both time and moneyand because the system is so versatile you canuse it almost anywhere.

The systems include:1. Cladding system available for insulated

brickwork2. Prefabricated non-insulated external

brickwork 3. Prefabricated internal decorative use.

HOW IT WORKSThe systems are suitable for larger developmentsor smaller domestic projects and are easilyinstalled by semi-skilled labor.

1. The insulated backer panel is supplied pre-laminated with a vacuum formed waterproofstyrene skin molded to form a template of

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horizontal tracks which locate the brick orstone slips.

Figure 1.57: Easy to slot and secured

Figure 1.58: A matching and quality work

2. This composite laminated panel is fixed tothe wall or frame using panel fastenersspecially designed to suit differentsubstrates.

3. A permanent bonding, weather-proofconstruction adhesive is applied to eachcourse.

4. Brick or stone slips, corners or speciallymade angles are then inserted between thetracks.

5. To complete the installation, our ownspecially formulated pointing mortar is pipedinto the joints and tooled as withtraditional brickwork.

TYPE OF BRICK CLADDING

BASIC BRICK SLIP INSTALLATIONFor relatively small projects such as fireplaces or plinths, brick slips can be boughtindividually or in packs. The easiest method forinstallation is the use of a suitable brickcladding adhesive. As with traditionalbrickwork, the end of the brickwork is built upfirst and string lines banded across to providea straight edge for the top of the bricks tomeasure to. Brick slips can be cut or staggereddepending on the pattern of the brickwork togive the correct bonding.

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With the brick slips fixed and dried withadhesive, the joints can be pointed as shownFigure 1.58. The pointing mortar is generallysupplied from the brick slip supplier and whenmixed can be applied into the gaps with acartridge gun or similar method. Pointing of thebrick slips is completed with finishing thejoints be removing the excess mortar as inFigure 1.59.

INSULATED BRICK SLIP PANELSVarious manufacturers of brick cladding alsoprovide insulated panels on which to attach thebrick slips. These panels provide a profiledbrick course and joint, giving the installer aquick, easy and accurate method in which toinstall the brick slips like in Figure 1.60. Thepanels are initially attached to the substrate,these fixing methods depend on the materialattached to and the type of project the brickcladding is being used for.

Figure 1.46: 3 dimension views of brick claddingsystems.

Figure 1.60: Insulated brick slip panels.

Fitting of the brick slips would begin with thecorner bricks or "pistols" and a calculationtaken to find out the number of bricks between

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the corners and the size of the mortar jointrequired. The 10mm vertical joint is taken bythe profile board which makes installation ofthe brick slips so much easier and quicker.Brick slips can be cut with a tile cutter ormanually to provide the correct spacing of thebrick slips. The brick slip adhesive should beallowed to dry fully before beginning thepointing.

Special pointing mortar is applied with a gun orcartridge and the excess removed, then cleanedby brushing the face of the brick slips.

MECHANICAL BRICK CLADDINGAnother method of fixing brick cladding or slipsis by mechanical technique. Their brikloc systemas shown in Figure 1.61 provides a mechanicaland mortar fix which can used on any substrate.This mechanical method works by locking thebrick slips in place and aligning the brickspreventing them from becoming loose or fallingoff. This mechanical brick cladding system isvery lightweight once installed and can be usedwith standard brick slips. With the uniquefixing method like in Figure 1.62, it is veryquick to install, saving time and money oncostly labor and site time.

PRE-FABRICATED BRICK SLIP CLADDINGSYSTEM

Pre-fabricated brick slip cladding system,enabling internal and external masonry to beassembled with speed and efficiency without theneed for specialist tradesmen in a huge range offinishes including brick, stone, marble,terrazzo and ceramics

CLAY BRICK PAVINGThe term "brick paver" generally describes anysegmental paving unit which relies uponinterlock as its principle mean of loaddistribution and is primarily used to pavedriveways, patios, pool decks, sidewalks, andstreets. In order to differentiate the type ofsegmental paving unit being used to pave theseareas, we determine whether the product is madewith clay or with sand.brick(noun)

1. A block of clay hardened by drying in the sunor burning in a kiln

pav-er(noun)2. A brick, tile, stone, or block used forpaving

Unfortunately, most people refer to pavers asbrick pavers, when in reality; the onlyoccurrence when that is an accurate descriptionof the product is when it is made of clay. The

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vast majority of pavers, however, are producedwith sand, not clay.

Figure 1.61: Mechanical brick cladding.

Figure 1.62: Fixing and finishing method ofmechanical brick cladding

Brick pavers typically look like bricks in bothcolor and shape. They are more frequentlyproduced in regions where clay is an accessibleand affordable natural resource.

Pavers on the other hand are produced with amixture of aggregates, small stones and pebbles,sand, color dyes, and grey or white cement.Since this type of paver production is more

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popular, there is a larger supply of productsthat cater to the demand. Comparatively,concrete pavers are much cheaper than their claycounterparts. Pavers made with grey cementproduce darker colors and because grey cement isa cheaper raw material, these darker colorpavers are cheaper than white cement, lightercolor pavers.

CLAY BRICK PAVERS ADVANTAGES

STRONG AND DURABLEPavers that were laid down over two centuriesago are still in active service. Why? Becausethere are only a few paving materials that canmatch genuine clay brick pavers for strength anddurability.

And the reason for that is that when clay paversare manufactured to today’s stringent standards,they are capable to achieving compressivestrengths of over 10,000 pounds (5 tons) persquare inch, and of weathering the harshestfreeze-thaw environments.

EASY TO LAYThe brick that the most people are familiar with- the face brick in houses – are laid with

mortar. Laying brick paving is the easiest andsimplest way to lay brick paving in a “flexible”set, laying the brick on a crushed stone base,with sand creating the interlock between bricks.

This system is actually less expensive than amortared paving system and more durable,because, unlike solid poured paving, itsflexibility means that it will never crack.

CHOICES OF DESIGN AND COLORSEach clay brick is as unique as a snowflake,deriving its natural color from the earth fromwhich it is made; the palette of brick isvirtually infinite.

When we think of brick, most of us think “red,”but brick pavers span the spectrum from creamsand buffs to dark charcoal, with most colors inbetween. When it comes to design, your onlylimit is your imagination and creativity.While most brick pavers are rectangular inshape, you can create intricateherringbone and basket weave patterns thatgo beyond the simple rectangle. You canfurther accentuate a design by "banding,"using brick of contrasting color, alongthe edges of a design like in Figure 1.63,1.64 and 1.65.

But rectangles aren't the only shapesavailable today. You can also get square

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or octagonal designs that further add tothe complexity of the look and design. Ifyou want clean, crisp lines, you canchoose an extruded paver. If you want tomirror the aged patina of antique brickwork, you can choose from antique paversdesign.

LONG LASTINGThe lines may have softened with age, butthe color is as fresh as the day thepavers were set down. And the reason isthat the color in a clay brick paver isthe color of the earth from which it ismade of, so that color is "through andthrough." With other kinds of pavingmaterial, the color that you see isactually created with a dye like in Figure1.66. Over time, the material carryingthat dye gradually erodes, making thesepavers appear to "fade."

ECONOMICThe keyword here is "too." Clay pavers area little more expensive than other pavingmaterials. But then they ought to be,because a genuine clay brick paver is apremium product that lends a premium aurato your home.

Figure 1.63: Pavers for walkways

Figure 1.64: Brick paving fix around swimming pool

Figure 1.65: Pavers for hardscape

To expect clay pavers to cost no more thancommon paving materials like asphalt andpoured concrete would be unrealistic, butlong after the asphalt and concrete need

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to be replaced, and the brick will stilllook as great as the day they were laid.Clay brick pavers are premium, value-addedproduct, giving years and years oftrouble-free service, and dramaticallyenhancing the curb appeal and value ofyour home.

When installed by a mason, theinstallation charges are the same for bothconcrete and genuine clay pavers. And, bychoosing a "flexible" installation, youcan lay them by yourself, eliminating theinstallation costs altogether.

It’s pretty obvious that brick pavers are in aclass of their own. Brick presents a quite butstately elegance that is warm and welcoming. Thebeauty of brick will never go out of style.Adding a brick walkway or driveway can also addgreat value to your home. In every way, when youchoose brick, your return is far greater thanyour investment.

Figure 1.66: Several design and colors ofclay pavers.TYPE OF BRICK PAVERSThe material used in this driveway was 4"x8"tumbled clay brick pavers. In order to accentthe field and ensure a durable surface fordecades to come, the builder accented thedriveway by pouring concrete curbs around theperimeter of the paver field. Although anunnecessary step for a paver drivewayapplication, this decision adds to theaesthetics of the clay paver driveway andguarantees a long term product for the client.

THIN PAVERS Thin pavers are an elegantly simple andaesthetic group of in products as Figure 1.67.Thin Pavers create a sophisticated and uniquelook without the large undertaking of removing

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existing surfaces and the mess that comes withit. Instead you can use this magnificent productas an overlay to a surface that has lost itsshine. Thin pavers are only one inch inthickness an can be applied on top of existingdriveways, patios, pool decks, asphalt and manyother surfaces. This convenience also has anadded bonus it is less expensive because it usesless material and there is less prep involvedwhich saves on labor costs.

THICK PAVERS Thick Pavers are a stronger solution for heavilytrafficked areas or areas that do not have anexisting surface. Most new constructionapplications use thick pavers for driveways,pool decks, patios, and sidewalks. Thick paversare stronger than thin pavers because they areover 2 times thicker, hence the name. Naturally,brick pavers are a more expensive solution andshould only be used if one of our expertsrecommends it for the particular application. Figure 1.68 is a picture that depicts how athick paver can be used for a topical solution.

PAVER SEALERPaver sealer is a transparent sealant thatprotects the paving from stains, inhibits weedgrowth, and, in the case of block paving,stabilizes the jointing sand. Paver sealer alsohas an aesthetic purpose; it gives pavers that

wet look year-round which really shows of theircolor and contrast. Paver sealer is highlyrecommended to keep your pavers looking new andprotect them for years to come as in Figure1.69.

Figure 1.67: Thin pavers

Figure 1.68: Thick pavers

Figure 1.69: Paver sealer used in installingclay pavers

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