choosing the right all steel gutter guard - blue mountain mesh · pests. left unchecked, clogged...

Choosing the right all steel gutter guard

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CORROSION RESISTANCE + A Blue Mountain Mesh Information Guide + + 2013

WHY ZINC-COATED STEEL SHOULD BE YOUR FIRST CHOICE

The harsh Australian environment really puts building materials to the test. The effects of extreme heat, storms, bushfire and living in coastal environments means architects, builders, property owners and tradespeople are all looking for materials that can withstand all kinds of environmental pressures.

Steel is a material that many people look to when choosing a gutter guard, because it is durable, cost effective and looks the part. Because once you’ve built a home, you need to look after it - protecting your investment and making the task of maintaining your property easier. Building a home needs to consider the whole life cycle of the building. A home that takes in its environment, is designed and built to perform efficiently, and minimise maintenance is important to maximise your long term investment.

One of the key areas for maintenance on a property is the roof and gutter. A build-up of leaves and other debris can cause significant maintenance issues, increasing the risks of flooding, bushfire, pest infestation and falls from ladders. A recognised way to prevent blocked gutters, and effectively manage these environmental and safety risks, is to install gutter guards (also known as gutter mesh).

With so many gutter guard products to choose from, consumers, builders and architects are keen to understand the key differences before choosing a product. Balancing needs of product quality, longevity, appearance and cost first requires an understanding of how steel gutter guards are made and installed, including the different manufacturing methods and materials used.

This paper will look at:

+ A comparison of manufacturing methods used by three popular gutter guard brands.

+ The corrosion myths around using all steel gutter guards.

+ Results from independent tests that confirm the corrosion resistance of Blue Mountain Mesh all steel gutter guards.

+ One of the key areas for maintenance on a

property is the roof and gutter.

+ Installing gutter guard is an effective way to

prevent blocked gutters, and effectively manage

many environmental and safety risks (flooding,

bushfire, pest infestation and falls from ladders).

+ There are lots of myths around using all steel

products as gutter protection.

+ Understanding the key differences in how gutter

guards are made will help you make an informed

choice.

+ Independent tests have confirmed that using

hot-dipped, zinc coated steel provides superior

protection against the weather and other

environmental risks.

Photo : CRAWFISH HEAD, Dec 2008



THE BENEFITS OF ALL STEEL GUTTER GUARDS Something as simple as ensuring your gutters are clean and clear is actually a very important factor in home maintenance. Without it, damage to your property could be a serious issue.

Gutters are the unsung heroes of your home, forming a vital part of home construction. The main function of a gutter is to remove or transport water away from the roof of your home – either into a drainpipe or water collection and storage system. Without gutters, water that falls on your roof can flow toward the walls, seep into cracks and get inside, causing extensive flood, moisture and structural damage.

A gutter does a good job of removing this water, so long as it is properly maintained. Blockages are common and gutters require ongoing maintenance to ensure they can function properly. A gutter filled with leaves and debris is also a dangerous source of fuel for bushfires; and can provide a haven for vermin and other pests. Left unchecked, clogged gutters can eventually lower the value of your property or result in extremely expensive repairs.

Experts generally recommend that you clean your gutters at least once every three months; and more frequently if leafy trees hang over your roof. This takes time and can be risky if you do it yourself; or expensive if you need to pay someone else to do this job for you.

A gutter guard provides a long term solution to solve this problem by preventing debris from

entering the gutter in the first place. The most advanced gutter protection systems use a fine yet strong steel mesh fitted to the roof to prevent leaves and other debris from entering the gutter.

Only the highest quality steel gutter mesh provides the strongest protection against the elements (wind, rain and hail) and is also non-combustible, which means it meets the Australian Standard for the Construction of buildings in bushfire-prone areas (AS3959-2009) (see Blue Mountain Mesh Information Guide Issue – Bushfire Building Compliance or Ember Attack Protection). Steel is also strong enough to withstand attack from the most persistent pests, including possums and birds that can infiltrate roof spaces and cause significant and costly maintenance issues (see Blue Mountain Mesh Information Guide Issue – Pest Control).

However, some consumers have been concerned about using steel gutter guards because they believe they will corrode, especially in coastal locations. With more than 8 in 10 Australians (85%) living within 50 kilometres of the coastline of Australia (ABS 2006), corrosion resistance is an important consideration.

WHAT IS CORROSION? Corrosion is the deterioration of metal as a result of chemical reactions between it and the surrounding environment. We generally use the term ‘rust’ to describe corrosion in iron and steel. The form and rate of corrosion depends on the type of metal and environmental conditions – particularly which gases are in contact with it.

Corrosion of steel is an electrochemical reaction that requires the presence of water (H2O), oxygen (O2) and ions such as chloride ions (Cl¯), all of which exist in the atmosphere. Atmospheric chloride ions are in greatest abundance anywhere near the coastline. This electrochemical reaction starts when atmospheric oxygen oxidizes iron in the presence of water.

In addition, the atmosphere also carries emissions from human activity, such as carbon dioxide (CO2), carbon monoxide (CO),

sulphur dioxide (SO2), nitrous oxide (NO2) and many other chemicals, which can also be significant in the corrosion process. If any two dissimilar metals are in contact with each other, the more reactive metal will corrode in preference to the less reactive metal (Key to Metals, 2013).

O2 O2OH- OH-Fe2+ Fe2+

e¯ e¯ e¯ e¯

WaterDroplet

The hydroxidequickly oxidizesto form rust

Electrochemicalcell action drivenby the energy of oxidation continuesthe corrosionprocess

Iron Hydroxideforms and precipitates

Cathode actionreduces oxygenfrom air, forminghydroxide ions

Anode actioncauses pittingof the iron

Ironelectron

�ow



GALVANIC OR DISSIMILAR METALS CORROSION

Galvanic corrosion is corrosion damage created when dissimilar materials are joined by a corrosive electrolyte. For example, steel and aluminium touching and an electrolyte such as salt-water or even rain water. This can happen on roofing where different metal products are used on roof and gutters.

When two different metals are in contact with a corrosive solution, (e.g. water) each will develop a corrosion potential and become positive/negative ends of an electric circuit. In this case, one metal will be the anode and one the cathode. The corrosion rate of the anode will be increased (e.g. zinc or aluminium will corrode faster and so is sacrificial) and the cathode will decrease (e.g steel will corrode less and is protected).

All environments are corrosive to some degree, although certain environments create more intense breeding conditions for corrosion than others. This includes areas where there is more water exposure, such as marine or coastal environments. However, the most common factor leading to corrosion, and eventual material replacement, is time (BlueScope Steel 2003a).

The table (right) shows a series of metals arranged in order of electrochemical activity in seawater (the electrolyte). This arrangement of metals determines what metal will be the anode and cathode when the two are put in a electrolytic cell. Metals higher on the scale provide cathodic or sacrificial protection to the metals below them. Therefore, zinc protects steel (American Galvanizers Association, 2013).

CORRODED ENDanodic or less noble

Magnesium

Zinc

Aluminum

Cadmium

Steel

Lead

Tin

Nickel

Brass

Bronzes

Copper

Nickel-Copper Alloys

Stainless Steels (passive)

Silver

Gold

Platinum

PROTECTED ENDcathodic or most noble

What is Galvanised Steel?Galvanised steel is steel that has gone through a chemical process to keep it from corroding. The steel gets coated in layers of zinc oxide because this protective metal does not get rusty as easily. The coating also gives the steel a more durable, hard to scratch finish that many people find attractive. For countless outdoor, marine, or industrial applications, galvanized steel is an essential fabrication component.

(Wisegeek 2013)

HOW DO WE PROTECT STEEL AGAINST CORROSION?

There are various ways to protect steel against corrosion. A common way involves using the reaction between dissimilar metals called ‘Sacrificial Protection, Cathodic Protection or Galvanic Protection’. The most widely used metal for this purpose is zinc, which provides a barrier between the steel substrate and corrosive elements in the atmosphere (e.g. water and gases).

Zinc is a great choice in protecting steel, as not only does it not allow moisture and corrosive chlorides and sulfides to attack the steel, it corrodes in preference to the steel at a generally slower rate. This is because zinc is more anodic than steel, which means the zinc will corrode first until it is entirely consumed, prolonging the life of the steel.

During the galvanisation process (i.e. when steel is submerged in melted zinc) a chemical reaction permanently bonds the zinc to the steel. The most external layer is zinc, but successive layers are a mixture of zinc and iron, with an interior of pure steel.

Furthermore, the zinc’s sacrificial action also offers protection where small areas of steel may be exposed due to cut edges, drill holes, scratches. This means that the cathodic protection of the steel continues until all the zinc is consumed.

Cathodic protection of the steel from corrosion continues until all the zinc is consumed

Exposed steel is protected



A MATTER OF FORM – NOT ALL STEEL GUTTER GUARDS ARE THE SAME

Not all steel gutter guards are created equal, and their difference comes from the way they are manufactured. Some steel gutter mesh products are formed by stretching sheets of steel and cutting small holes in it to make ‘mesh’/apertures which leaves a myriad of edges which are not zinc coated and therefore subject to rust. There are many steel gutter guard products on the market that do not use a galvanizing system where this method of manufacturing would be a cause for concern.

The most advanced gutter guard manufacturers use a hot dip galvanised system, where the product is coated in zinc, which adds to the corrosion protection. In this method, the act of galvanising steel causes zinc compounds to build up at cut edges by an electrolytic reaction whenever water or moisture is present. The effect is that these zinc compounds slow the rate of corrosion for the underlying metal if there were cut areas present (BlueScope Steel 2003a).

COLORBOND® steel combines the best of modern steel making technologies, developed over decades by BlueScope Steel.

1. We start with a ZINCALUME® steel base. ZINCALUME® steel has a zinc/aluminium alloy coating that delivers outstanding anti-corrosion performance.

2. We apply a conversion layer to the surface of the steel to improve adhesion.

3. We then bake a polyester primer onto the surface.

4. Finally, we apply the top coat - a specially developed, exterior grade paint that is baked on to ensure maximum resistance to chipping, peeling and cracking.

COLORBOND® steel is made using Super Polyester coating technology, ensuring the painted finish retains its “as new” look for longer.

A COMPARISON OF THREE LEADING ALL STEEL GUTTER MESH / GUTTER GUARD PRODUCTS1. COLORBOND® Steel Gutter Guard manufactured from COLORBOND® SteelCOLORBOND® Steel is a preferred product for roofing and fencing Australia wide and has an extremely strong brand name. Due to this strong brand name, a number of gutter guard suppliers supply and install COLORBOND® steel gutter guards made from COLORBOND® steel, but COLORBOND® steel was not designed to be used as a gutter guard, and is not really fit for purpose as a gutter guard.

The main reason is due to the production process, specifically in the expansion process, during which the coil is cut and slit to create apertures – or holes – to form the mesh. In this process the polyester primer and the top coat of the COLORBOND® steel are broken, leaving the ZINCALUME® steel base exposed. This exposed base is now open to rust, leaving the gutters open to rust when placing the COLORBOND® steel gutter guard made of COLORBOND® steel on the gutters on the roof.

Reference : How is COLORBOND steel made. www.colorbond.com/technology/colorbond-steel/how-is-it-made



2. Gutter Guard made from ZINCALUME® Steel Mesh

Some ZINCALUME ® steel mesh gutter guards have a similar appearance to the various COLORBOND® steel gutter guards made

from COLORBOND® steel, but there are two main differences between this type of mesh and the COLORBOND® steel gutter guard

made from COLORBOND® steel:

+ Stretched/expanded from ZINCALUME® steel, not COLORBOND® steel

+ Powder coated after the expansion and cutting process to cover all edges and surfaces of the mesh, both front and back

Some gutter guard manufacturers claim that by using ZINCALUME® steel (zinc/aluminium alloy-coated steel) and 360 degree powder

coating gives the product the protection of a total coating. However, experts have questioned the claims that ZINCALUME® steel

has a longer lifetime than hot dip galvanised steel – with some suggesting that to claim its protective properties are superior to hot dip

galvanized steel would be both ‘misleading and irresponsible’ (Hot Dip Galvanizing Today, 2005).

COLORBOND® steel combines the corrosion resistance of a ZINCALUME® steel base with a durable, oven baked paint finish.

AN EXTRACT FROM THE ARTICLE “ZINCALUME VERSUS HOT DIP GALVANIZING” (Hot Dip Galvanizing Today, 2005)

OTHER FACTORS THAT NEED TO BE CONSIDERED

Formability: The zinc/aluminum coating is more prone to damage and cracking than a pure zinc coating, particularly where thicker steel sections are involved. This can result in micro cracking of the coating when severe bending or forming takes place.

Edge protection: The cathodic protection provided by the hot dip galvanizing process is substantially more effective than that available from the Zinc Aluminium coating. Steel sections in excess of 0.6mm thickness will display distinct rust staining on cropped edges. In the case of the general hot dip galvanizing process, such problems do not apply in that all surfaces are provided with a protective coating.

Summary:The zinc/aluminum coating (Zincalume) is an excellent coating in most environments when used, for example, as roof sheeting. To claim that its protective properties are superior to the substantially thicker and metallurgically different hot dip galvanized coating applied to fabricated products would be both misleading and irresponsible.

Feature

"Zincalume" versus hot dip galvanizingthat available from pure zinc.

Apart from the added protection

provided by the iron/zinc alloys, it must

be borne in mind that this coating is

some 5 times thicker than that provided

by the "Zincalume" coating.

For these reasons, the claim that a life

of four times greater is obtainable from

"Zincalume" is most certainly not

applicable to hot dip galvanizing as

applied by the general hot dip

galvanizing process.

Other Factors that need to be

considered

Formability:

The Zinc Aluminium coating is more

prone to damage and cracking than a

pure zinc coating, particularly where

thicker steel sections are involved. This

can result in micro cracking of the

coating when severe bending or forming

takes place.

Edge Protection:

The cathodic protection provided by the

hot dip galvanizing processes is

substantially more effective than that

available from the Zinc AIuminium

coating. Steel sections in excess of

0.6mm thickness will display distinct

rust staining on cropped edges. In the

case of the general hot dip galvanizing

process, such problems do not apply in

that all surfaces are provided with a

protective coating.

Summary:

The zinc / aluminium coating

(Zincalume) is an excellent coating in

most environments when used, for

example, as roof sheeting. To claim

that its protective properties are

superior to the substantially thicker and

metallurgically different hot dip

galvanized coating applied to fabricated

products would be both misleading and

irresponsible.

The zinc / aluminium coating as applied

to continuously coated steel sheet

provides excellent corrosion resistance

in the case of atmospheric exposure in

most environments. The same does not

of course pertain in buried or immersed

conditions where the corrosion

mechanism of selective leaching can

significantly influence the corrosion

resistant life of this coating. For

atmospheric exposure, the claim is

made that "Zincalume" will provide a

lifetime of up to four times that of hot

dip galvanized steel under the same

conditions. This claim is no doubt

correct when it comes to comparing

normal continuously hot dip galvanized

steel e.g. roof sheeting with material

onto which the Zn/AI coating has been

applied by means of a similar process.

The bland statement that "Zincalume"

steel has a lifetime of up to four times

that of hot dip galvanized steel is,

however, nebulous and, hence,

misleading since it does not define

coating thickness or for that matter the

difference in coating structure

obtained from the hot dip galvanized

coating applied after fabrication to that

obtained on continuously hot dip

galvanized coil. The following

technical information is given with a

view to providing a transparent and

unbiased picture.

Continuously hot dip galvanized steel

coil (Zendzimir Process). The zinc

coating applied on this material in

general use is referred to as Z275 i.e.

275g/m2 of zinc or more accurately

137.5g/m2 per side. Converted into

coating thickness, this yields an average

thickness between 18 and 20 microns

per side of a relatively pure zinc coating

where iron/zinc alloys are virtually

absent.

Furthermore, the specification makes

allowances for only 40% of the

individual value (235g/m2) i.e. 13.5µm to

be found on one side.

The claim that a "Zincalume" coating

will provide up to four times the life of

this coating in atmospheric exposure is

probably correct from a barrier

protection aspect.

General Hot Dip Galvanizingafter Fabrication

This process provides a coating

thickness of 60 to 80 microns on

relatively thin steel sections such as

that used for the manufacture of

palisade fencing. Added to this, the

coating structure consists of between

50% and about 80% iron/zinc alloys,

which provide 30% greater corrosion

resistance in most environments than

The edge protection properties provided by a zinc / aluminium coating are substantially less thanthat provided by a hot dip galvanized coating.

48 Hot Dip Galvanizing Today Volume 2 Issue 2 2005



Cross section of Blue Mountain Mesh – showing the layers of strength the product is made Blue Mountain Mesh is

manufactured by weaving and welding steel to form a mesh, before it is put through a process of hot dipped zinc coating, priming, painting and oven baking to deliver a coating thickness that provides superior corrosion resistance.

3. Hot Dipped Zinc Coated All Steel Mesh Gutter Guard

By contrast, Blue Mountain Mesh is manufactured by weaving and welding steel to form a mesh, before it is put through a process of hot dipped zinc coating, priming, painting and oven baking to deliver a coating thickness that provides superior corrosion resistance. Its unique woven and welded design eliminates all concerns regarding corrosion from cut edges.

All the edges on Blue Mountain Mesh are covered in the manufacturing process. Unlike other steel mesh, there are no concerns regarding cut edges as the mesh itself is formed using base wire, galvanised steel, primer and paint. These layers provide additional protection to the base wire, provided that each layer is evenly distributed and properly sealed. This is an advanced manufacturing process that, combined with proper installation methods, affords the highest level of gutter protection.

Furthermore, the zinc’s sacrificial action also offers protection where small areas of steel may be exposed due to drill holes or scratches. This means that the cathodic protection of the steel continues until all the zinc is consumed.

HOW LONG WILL STEEL MESH GUTTER GUARD LAST?

Anyone considering installing a gutter guard at their home will ask the same question. How long will this product last? Of course, their concern relates to how well they will be protected for their investment. Not all manufacturers will know the answer to this question, despite offering warranties between 10 and 25 years for their products.

Blue Mountain Mesh has commissioned independent tests through UniQuest and the CSIRO to support their claims that their All Steel mesh products meet relevant Australian Standards around zinc coating, corrosion, blistering and cracking; and to give homeowners, retailers, installers and other industry professionals confidence around the longevity of the all steel product.

So what did they test, and how did the all steel mesh perform?



TEST TYPE

Coating thickness and consistency test

i.e. How reliable is the coating?

Longevity test

i.e. How long will it last?

Weathering test

i.e. How well does it withstand the weather?

Prohesion testing

i.e. How well does it withstand the weather?

METHOD USED

High resolution microscopy was used to determine base wire thickness and nature, thickness and consistency of wire coatings.

Microscopic measurements were used to estimate how long the anti-corrosive coating will last in various environments based on the mass of zinc coating used.

A QUV Weathering Tester was used to subject the products to UV light and salt spray exposure equivalent to a period of 12 years outdoors.

A method of cyclic accelerated corrosion that relates more closely to long term natural exposure than conventional salt spray, humidity or sulphur dioxide tests.

THE RESULTS

The test confirmed that Blue Mountain All Steel Mesh Gutter Guard meets the Australian Standard AS/NZS 4534:2006, Zinc and zinc/aluminium-alloy coatings on steel wire. Each corrosion-resistant layer of material was found to be well-bound and continuous, preventing environmental elements such as sunlight and rain penetrating the base wire and causing rust and decay (UniQuest 2006).

Tests confirmed the coating on Blue Mountain All Steel Mesh Gutter Guard will last well in excess of the 12 year warranty period. In fact, the tests offered a projected life expectancy of up to 60 years in moderate climates with light industrial pollution or very light marine influence (e.g. includes Melbourne, Adelaide and Hobart; as well as inland cities such as Ballarat and Canberra); and up to 25 years in ocean-front towns and cities situated up to 30km from the shore (UniQuest 2006).

The tests concluded that there was no evidence of failure or corrosion of the steel on Blue Mountain All Steel Mesh Gutter Guard, with the zinc coating offering superior anti-corrosion qualities (UniQuest 2006).

At completion, the samples showed no signs of red rust, blistering or cracking of the undercoat or topcoat. Blue Mountain All Steel Mesh Gutter Guard therefore meets the Australian Standards for Degree of corrosion (AS 1580 481), Degree of blistering (AS 1580 481.1.9), and Degree of cracking (AS 1580 481.1.10) (CSIRO 2012).

RESULTS OF BLUE MOUNTAIN MESH’S INDEPENDENT TESTING

Steel coupons in salt fog chamber. Photo : KARL PULTKE Mar 2006

Blue Mountain Mesh has commissioned independent tests through UniQuest and the CSIRO to support their claims that their All Steel mesh products meet relevant Australian Standards around zinc coating, corrosion, blistering and cracking



ATMOSPHERIC CLASSIFICATION

Mild

Moderate/ Tropical

Industrial

Marine

Severe Marine

ISO CATEGORY

1-2

2

3-4

3

4

DESCRIPTION

Areas far inland

Inland other thanfar inland

Areas around majorindustrial complexes

Areas influenced bycoastal salts

Begins anywhere from 100-400 metres in from the beach front of breaking surf and can extend inland

INDICATIVE LIFE (YEARS)

60-140

25-60

8-25

12-25

3-12

Tests confirmed the coating on Blue Mountain All Steel Mesh Gutter Guard will last the 12 year warranty period.

In fact, the tests offered a projected life expectancy of up to 60 years in moderate climates … and up to 25 years in ocean-front towns and cities situated up to 30km from the shore (UniQuest 2006).

The results show that, Blue Mountain Mesh’s 12 year warranty is a very conservative estimate based on exposure in the most demanding marine environments. Independent test results from UniQuest demonstrate that it is suitable in a wide range of environments and will last from 12 – 60 years, as reported in UniQuest’s corrosion AS/NZS 4534:2006 test findings below:

MILDISO Category 1-2

Areas far inland

MODERATEISO Category 2

Inland other thanfar inland

INDUSTRIALISO Category 3-4

Areas around majorindustrial complexes

MARINEISO Category 3

Areas in�uenced bycoastal salts

SEVERE MARINEISO Category 4

Begins anywhere from100-400meters from the beach front of

breaking surf and can extend inland



HOW CAN THE RH GROUP HELP?The RH Group is an Australian company driven to help every person and every community make the most of their environmental assets.

We design, manufacture and wholesale high quality and sustainable water, environmental and trade products for Australian and international markets. We work with governments, retailers, distributors and consumers all over the world to find smarter, more innovative solutions to challenges created by our environment, and in doing so, create more sustainable futures.

Our Blue Mountain Mesh advanced gutter protection system offers homeowners protection from a range of environmental hazards, including flooding during storms and ember attack during bushfire.

ABOUT BLUE MOUNTAIN MESHBorn out of fire: The inspiration behind Blue Mountain Mesh’s all-steel gutter mesh came from the most tragic circumstances: watching a man trying in vain to save his family home from a savage bushfire. As the man struggled to put out the flames that had erupted in the roof gutters of his home, extreme gusts of wind blew more burning embers onto his roof. Fueled by an abundance of leaves and debris in the home’s gutters, his efforts to extinguish the fire with his garden hose were futile. While none of his family were injured in the blaze, the home and all belongings were lost.

Blue Mountain Mesh products prevent leaves and debris from entering gutters and downpipes. The all steel, fire resistant gutter mesh minimises gutter maintenance and improves the quality of rain water collected for tanks. The proprietary hot dipped zinc coated and oven baked manufacturing process offers superior corrosion and heat resistance, providing superior protection for homes over the longer term.

We look forward to opportunities to help more Australians reduce risk and protect themselves and their greatest assets. For more information on our all steel, custom-made gutter protection products visit www.bluemountainmesh.com.au or call 1800 612 908.

WHY CHOOSE BLUE MOUNTAIN MESH?

+ Blue Mountain All Steel Gutter

Mesh® is hot dipped galvanised,

zinc coated steel which provides a

corrosion resistant layer.

+ Our zinc coated corrosion

resistant steel mesh is strong and

durable and will stand the test of

time

+ Our entire range is bushfire

compliant and conforms to

the Australian Standard for the

Construction of buildings in

bushfire-prone areas (AS3959-

2009) and the updated Australian

Standard for the ember guard

protection of sheet roofs

(AS3959-2009/Amdt 2011).

+ Our unique steel profile ensures

our steel mesh lies perfectly flat

and means the finished product

looks like a seamless addition to

your roof.

+ Our mesh fits all gutter profiles

and can be adapted for all roof

types, custom made and available

in a choice of over 30 colours.

+ We offer a 12 year warranty based

on minimum performance that

we expect from our product.

Results from independent tests

offer a far longer projected life

span with 12 years being the most

conservative estimate.



REFERENCESAmerican Galvanizers Association 2013, Sacrificial Anodes, accessed 13th September 2013, http://www.galvanizeit.org/corrosion/corrosion-protection/sacrificial-anodes/.

Anzor 2013, Galvanic Corrosion: keep those metals apart, 12 Febrary 2013, accessed 11 September 2013, <http://www.anzor.com.au/blog/galvanic-corrosion-keep-those-metals-apart/>.

Australian Bureau of Statistics 2006, How many people live in Australia’s coastal areas?, accessed 22 April 2013, <http://www.abs.gov.au/ausstats/[email protected]/0/0ec9360424ea347eca256dea00053a70?OpenDocument>.

BlueScope Steel 2003a, Corrosion, General Introduction, Technical Bulletin CTB-1, 3 November, accessed 31 July 2013, <http://steelproducts.BlueScopesteel.com.au/files/CTB-1.pdf>.

BlueScope Steel 2003b, Cut Edge Protection of Zinc-Coated and Zinc/Aluminium Alloy-Coated Steel, Technical Bulletin TB-10, 5 November, accessed 31 July 2013, <http://steelproducts.BlueScopesteel.com.au/files/TB-10.pdf>.

COLORBOND® STEEL 2013, How is COLORBOND® STEEL® steel made?, accessed 31 July 2013, <http://www.colorbond.com/technology/colorbond-steel/how-is-it-made>.

CSIRO 2012, Test Report XC3112, Prohesion testing of mesh samples, CSIRO Materials Science and Engineering, Australia, 1 February.

Key to Metals 2011, Corrosion protection of Steel, accessed 31 July 2013, <http://www.keytometals.com/page.aspx?ID=CheckArticle&site=kts&NM=300>.

Marshall, P 2013, Galvanic Corrosion, accessed 31 July 2013, <http://philipmarshall.net/Teaching/rwuhp382/metals/galvanic_corrosion.htm>.

UniQuest 2006, Assessment of Mesh Assay by Spectrometer Services and rating of coating thickness by AS 4534, Australia, 10 September.

What is galvanized steel 2013, accessed 31 July 2013, <http://www.wisegeek.com/what-is-galvanized-steel.htm>.

Zincalume versus hot dip galvanizing 2005, Hot Dip Galvanizing Today, Volume 2, Issue 2, accessed 31 July 2013, <http://www.hdgasa.org.za/Journals/HDGASA%20V2E2.pdf>.

COLORBOND® and ZINCALUME® steels are registered trade marks of BlueScope Steel Limited.

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