understanding waterproofing
DESCRIPTION
This presentation gives an overview of the critical elements of waterproofing. What is waterproofing? Why waterproof? Where to apply waterproofing? Types of waterproofing.TRANSCRIPT
TheThe Principles of Waterproofing
Grace Construction Products
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Understanding the Critical Elements of Waterproofing
What is Waterproofing?
Why Waterproof?
Wh A l W fi ?Where to Apply Waterproofing?
Types of Waterproofing
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What is Waterproofing?
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Waterproofing vs Damp-proofing
Often the terms Waterproofing and Damp-proofing are incorrectly interchanged. According to ASTM definitions:
• Waterproofing is the treatment of a surface to prevent the passage of li id t i th f h d t tiliquid water in the presence of hydrostatic pressure.
• Damp-proofing is the treatment of a surface to retard the absorption of moisture in the absence of hydrostatic pressure.
Virtually all building envelopes, particularly below-grade areas and plaza decks, encounter hydrostatic pressure from water during their lifetimeduring their lifetime.
Therefore, the use of a quality waterproofing system is essential y g yto preserve the water-tightness of the building envelope.
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Waterproofing As Vapour Barrier
Is it important that a waterproofing membrane also be a vapour barrier?
Many waterproofing products are vapour barriers. Some are not.
Unimpeded water vapour will pass through concrete.
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What Is A Quality Waterproofing System?
A waterproofing system which prevents the passage of liquid water in the presence of hydrostatic pressure.
Protection as necessary.
A drainage system that reduces hydrostatic pressure.
Accessory products which complement, attach and detail theAccessory products which complement, attach and detail the waterproofing and drainage.
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Why Waterproof?
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Why Waterproof Your Structure?
The problem – substrates shrink, move and crack.
Rain water orRain water or building run-off
Soil
Gravel backfill
Foundation wall
High water table
P i t Base
Floor
Perimeter drainage system
Normal water table
Footing
Base
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Water Ingress Mechanisms
Ground level
Water table
Permeation
Seepage through joint or crack
Wetting & drying Permeation50% RH, 20oC
Wick action
P ti
Salts in drainage
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Permeation
How Water Can Penetrate Concrete Structures?
HoneycombsConcrete Structure
Large voids Cracks Joints Capillary action Hydrostatic g p ysucks water intopores
ypressure forces water into pores
P t ti th h O i P t ti th h C tPenetration through Openings Penetration through Concrete
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Intrinsic CracksPlastic settlement1
Plastic shrinkage2
3 Early-age shrinkage
4 Crazing
5 Alkali aggregate reaction
6 Shear3
3
7 Flexural
8 Thermal Shock
9 Kickers
1
2 2
3
4
5
9
7
10 Tie Holes1
2
3
3
3
3
6
8
9
10
3
3
3
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Why Waterproof Your Structure?
Liability issues
Structural integrity
Consequential damageConsequential damage
Provide additional usage space
Unexpected water sources (grade, sewer lines)
There may be a tendency to select and install a waterproofing system that has a lower initial cost. This may result in lower performance standard.y p
In addition to initial cost, attention should be given to the cost of repairing or replacing waterproof system failing prematurely and to other costs associated with the failure.
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Singapore Standard CP82:1999
Where to Apply Waterproofing?
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Where To Apply Waterproofing
Positive Side Waterproofing
Negative Side Waterproofing
Blind Side Waterproofing InteriorBlind Side Waterproofing
Interior Applications
Exterior Applications
Interior applications
External applications
Positive / blindPositive / blind side waterproofing
Positive sideNegative side
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Positive side waterproofing
Negative side waterproofing
Positive Side Waterproofing
Positive side is same side of the structure as the source of the water.
Designed to stop water before it has a chance to enter the structure and cause structural damage.
Typically the most effective solution.
Preprufe® Pre-applied
Silcor® Liquid Waterproofing
Waterproofing
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Negative Side Waterproofing
Interior side opposite the water pressure side of the structure
Most commonly used in• Remedial work
• Elevator pits
• Tank liners• Tank liners
Waterproofing Membrane
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Blind Side Waterproofing
Positive side applied prior to installing the structural walls or slabs.
Typically inaccessible once the structure is complete.
In many cases this is the only positive side waterproofing option.
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Interior Applications
Positive Side Waterproofing• Split Slabs
B th
Negative Side Waterproofing• Elevator pits
R t fit• Bathrooms
• Laboratories
• Mechanical rooms
• Retrofit
• Kitchens
• Fountains
• Planters
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Exterior Applications
Positive Side Waterproofing• Foundation walls• Plaza decks
Blind Side Waterproofing• Soil retention systems
P t llPlaza decks• Tunnels• Parking decks• Balconies
• Party walls
• Cut and cover tunnels
• Under slab• Balconies• Bridge decks• Planters
R fi
• Elevator pits
• Underpinning
• Roofing
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Types of Waterproofing
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Types of Waterproofing
Sheet Membrane Waterproofing• Lose laid – PVC, HDPE, etc.
• Bonded – self-adhesive, hot applied, pp
Liquid Waterproofing• One or two component
A li d b h d b• Applied by hand, by spray
• Hot applied, cold applied
Bentonite Waterproofing
Metal Oxide Waterproofing
Cementitious Waterproofing
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Waterproofing – Sheet Membrane or Liquid?
LapsControlled, guaranteed thickness
DisadvantagesAdvantages
No mixing or specialist equipment
Complex detailingRobust, self-reinforcedSheet Membrane
Trafficked immediately
q p
Q i k ith
Cure timeGood for complex geometries
Variable thicknessSeamless
Liquid
Minimal substrate preparation
Mixing and spray equipmentQuick coverage with spray application
q
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Bentonite Waterproofing
Bentonite panels
Geotextile encapsulated
HDPE / BentoniteHDPE / Bentonite
Reactive systems• Rely on water to activate and to
i tiremain active
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Metal Oxide and Cementitious
Primarily Portland cement-based materials
Positive and negative side applications
Inflexible, subject to cracking
Low costLow cost
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Summary
What is Waterproofing?• Prevention of water and vapour ingress
Why Waterproof?Why Waterproof?• Structures crack and move
• Subject to water pressure at some time in life cycle
Where to Apply Waterproofing?• Positive or negative
• Positive preferred
Types of Waterproofing• Sheet membrane, liquid, Bentonite, cementitious
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