Waterproofing sealants are materials that are applied to surfaces and joints to create a barrier against water infiltration. They are commonly used in various construction applications, including roofs, windows, doors, bathrooms, and basements. Here are some key points about waterproofing sealants:
Contact Information
Durotech Industries, 14 Essex Street Minto NSW 2566 Australia
02 9603 1177
sales@durotechindustries.com.au
https://www.durotechindustries.com.au/
Waterproof Membranes at Best Price in Australia 📞+61 1800 418 495 kodexcc
https://kodexcc.com/products/waterproofing-membranes
Explore Kodexxc's waterproofing membranes for durable and reliable solutions, perfect for your
buildings protection. Contact us today 1800 418 495 for membranes.
Protection: They protect structures from water damage, which can lead to decay, mold growth, and structural compromise.
Durability: Waterproofing membranes enhance the lifespan of buildings by preventing deterioration caused by water exposure.
Energy Efficiency: Proper waterproofing can improve insulation and reduce energy consumption by preventing moisture-related heat loss.
Cost Savings: Effective waterproofing reduces the need for costly repairs and maintenance caused by water damage.
Health and Comfort: Waterproofing helps maintain indoor air quality by preventing mold and mildew growth, enhancing occupant health and comfort.
This includes different method of treatments given in the time of building construction like : Anti termite treatment, water proofing, fire proofing, acoustical architectural, thermal insulation etc.
Screeds provide a vital layer in a floor that bonds the finish people see and walk across to the concrete substrate of the building’s construction.
If properly applied and maintained then most screeds need never be seen until the building comes to the end of its life and is dismantled. However failures in the planning, application, curing or drying processes can lead to later, potentially very costly, problems.
Read Flowcrete's whitepaper for an overview of the reasons for screed failure in both commercial and industrial environments, as well as an insight into screed failure avoidance and repair.
Waterproof Membranes at Best Price in Australia 📞+61 1800 418 495 kodexcc
https://kodexcc.com/products/waterproofing-membranes
Explore Kodexxc's waterproofing membranes for durable and reliable solutions, perfect for your
buildings protection. Contact us today 1800 418 495 for membranes.
Protection: They protect structures from water damage, which can lead to decay, mold growth, and structural compromise.
Durability: Waterproofing membranes enhance the lifespan of buildings by preventing deterioration caused by water exposure.
Energy Efficiency: Proper waterproofing can improve insulation and reduce energy consumption by preventing moisture-related heat loss.
Cost Savings: Effective waterproofing reduces the need for costly repairs and maintenance caused by water damage.
Health and Comfort: Waterproofing helps maintain indoor air quality by preventing mold and mildew growth, enhancing occupant health and comfort.
This includes different method of treatments given in the time of building construction like : Anti termite treatment, water proofing, fire proofing, acoustical architectural, thermal insulation etc.
Screeds provide a vital layer in a floor that bonds the finish people see and walk across to the concrete substrate of the building’s construction.
If properly applied and maintained then most screeds need never be seen until the building comes to the end of its life and is dismantled. However failures in the planning, application, curing or drying processes can lead to later, potentially very costly, problems.
Read Flowcrete's whitepaper for an overview of the reasons for screed failure in both commercial and industrial environments, as well as an insight into screed failure avoidance and repair.
A ready-to-use, liquid damp-proof
membrane which provides a seamless,
passive radon barrier.
It also acts as a barrier against the
gases methane and carbon dioxide.
Special Treatments required for building constructionUjasPandya2
various special treatments like termite treatments, damp proofing, fire protections, acoustics etc required in building construction in civil engineering. Essential treatments before and after construction of residential as well as public buildings. Services essential for building construction for maintenance and long life of building
This book describes concrete curing process; why the need to cure concrete works and how to deal with it. This book is among the site books one must have to perfect his/her work.
Learn everything about car park protection at http://marispolymers.com/products/flooring-systems/waterproofing-car-parking-flooring-systems/
Maris polyurethane products offer great car park protection. Highly permanent elastic membranes with excellent mechanical,thermal and UV resistance properties.
WATER PROOFING FOR BUILDING
The treatment given to prevent leakage of water from external source is generally termed as WATER PROOFING.
Usually extensive waterproofing measures are added to a building at the time of construction ,to provide moisture control form starting.
Waterproofing may also be done after a building is built ,to address problems as they emerge or as part of building retrofit.
A fully bonded waterproof coating based on polyurethane technology
Find out more about RIW Flexiseal typical uses and benefits here:
http://www.riw.co.uk/products/liquid-applied-systems/Flexiseal
If cracks develop while curing, this has a long-term negative impact on the concrete service life.
You can improve crack prevention at time of pour, and maximize concrete service life.
#futureof #concrete_curing #hydrogel
Which Waterproofing Method Should You Opt For?White metalco
Discover the optimal waterproofing method for your project. Explore sealants, membranes, and more to ensure effective protection against water damage. Make the right choice for long-lasting safeguarding.
A ready-to-use, liquid damp-proof
membrane which provides a seamless,
passive radon barrier.
It also acts as a barrier against the
gases methane and carbon dioxide.
Special Treatments required for building constructionUjasPandya2
various special treatments like termite treatments, damp proofing, fire protections, acoustics etc required in building construction in civil engineering. Essential treatments before and after construction of residential as well as public buildings. Services essential for building construction for maintenance and long life of building
This book describes concrete curing process; why the need to cure concrete works and how to deal with it. This book is among the site books one must have to perfect his/her work.
Learn everything about car park protection at http://marispolymers.com/products/flooring-systems/waterproofing-car-parking-flooring-systems/
Maris polyurethane products offer great car park protection. Highly permanent elastic membranes with excellent mechanical,thermal and UV resistance properties.
WATER PROOFING FOR BUILDING
The treatment given to prevent leakage of water from external source is generally termed as WATER PROOFING.
Usually extensive waterproofing measures are added to a building at the time of construction ,to provide moisture control form starting.
Waterproofing may also be done after a building is built ,to address problems as they emerge or as part of building retrofit.
A fully bonded waterproof coating based on polyurethane technology
Find out more about RIW Flexiseal typical uses and benefits here:
http://www.riw.co.uk/products/liquid-applied-systems/Flexiseal
If cracks develop while curing, this has a long-term negative impact on the concrete service life.
You can improve crack prevention at time of pour, and maximize concrete service life.
#futureof #concrete_curing #hydrogel
Which Waterproofing Method Should You Opt For?White metalco
Discover the optimal waterproofing method for your project. Explore sealants, membranes, and more to ensure effective protection against water damage. Make the right choice for long-lasting safeguarding.
2. Who is DUROTECH and What We
Believe
Durotech Industries is a leading manufacturer and supplier of waterproofing, sealants and
adhesive technologies. Durotech Systems products have been widely used in the
construction industry for the sealing and coating of both residential, commercial and
industrial buildings for over 44 years.
At Durotech we don’t believe that one product can do it all but we do believe a Durotech
System can.
3. • Identify some of the major failures of waterproofing membranes
• Identify the importance of using compatible full waterproofing system in
building particular end use areas
OBJECTIVES
• Evaluate why current waterproofed areas leak and identify the
defects hidden in waterproofing membrane and how to eliminate
them
• Describe how to identify what products can be used in particular end
use areas
4. Did you KNOW?
1%
80%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
Waterproofing Building Complaints
Construction vs. Maintenance
1%
99%
Construction Costs
Waterproofing Other
80%
20%
Maintenance Costs
Building Complaints due to Improper
Waterproofing
Other
Waterproofing is generally approximately 1% of
a total construction cost.
Unfortunately it is the cause of approximately
80% of building complaints.
5. • Substrate type
• Internal/external
• Flexibility Class
• Abrasive resistance
• Root resistance
• Curing time
• Ease of use & Environmental impact
Points to consider when selecting a membrane system
and why?
• Moisture content.
• Toxicity (safety)
• Pre membrane preparation
• One part or two part.
• Does it need reinforcing.
• Bond breaker or fillet
• Compatibility with adhesives & Cost
6. Bodycoat 2
Bodycoat 1
Primer basecoat
Things to note when waterproofing WET areas
Substrate
• Correct surface preparation and priming
• The membrane must not be affected by
structural movement
• Bond breaker will need to be installed
• The use of leak-proof flanges to house
floor grate and taps
• The must be allowed to cure before tiling
• Final Dry film thickness must be between
1 and 1.5mm
• Follow the manufacturer's instructions
7. What is Priming and why is it so important?
Image copyright @ Durotech
Surface preparation and priming are essential processes
to ensure adequate bond, even membrane film
thickness and overall performance. Cleaning the
substrate will remove any latience, oils, contaminants
and DUST. Dust is a killer, and can result in substrate
bond failure, blistering and pin holing. Primers were
never meant to be a dust suppressant, and dust
contamination must be removed prior to priming.
Solvent based membranes require a dry, dust free
substrate. Vacuuming and cleaning with a solvent based
primer are recommended for dry substrates, however,
washing with water and applying a water based hydro
epoxy will remove all dust and stabilise a damp
substrate against rising damp.
8. Areas should only be primed as they are about to be
coated with membrane. The primer should dry, but not
cure out to the point of losing activity or being dust
contaminated.
Hardy’s Scyon sheeting and other resin infused building
boards require specialised primers that are compatible
with the board’s resin. Damp Scyon or CFC sheeting
should be primed with an Epoxy primer, to stabilise
rising damp and high moisture content in the sheet.
Most Epoxy primers cannot be over-coated until the day
following application.
9. Liquid applied membranes fall into the following type of
classifications:
Wet Film
Thickness
(microns)
Dry Film Thickness after Full Cure (microns)
100% solids 80% solids 60% solids
500 500 400 300
750 750 600 450
1000 1000 800 600
1500 1500 1200 900
Wet and dry film thickness
Knowing the solid content of liquid applied membranes allows applicators to gauge the final dry film thickness, and monitor compliance
with manufacturer requirements. This is one of the more critical aspects of membrane application, as membranes that are applied too
thin will compromise elongation properties and reduce resistance to abrasive damage. This is one of the major concerns of all membrane
manufacturers, where a large proportion of applicators continually apply liquid membranes too thin, and then blame the product for
failure.
10. What is curing of the membrane and why is it
important?
Image copyright @ Durotech
Liquid applied membranes will have both a dried state and a cured state.
As with primers, an activity window may apply, where a solvent may be
required to reactivate the membrane for subsequent coats.
Curing of water based membranes relies on evaporation of the water out
of the membrane, leaving solid resin behind as a dry film. Curing is
therefore dependent on ambient humidity, temperature and airflow. High
humidity and low temperatures may slow membrane dry-out rates. Direct
heat should never be applied to membranes while curing as it may result in
blistering. Excessively hot substrates may cook the membrane, like an egg,
and result in
blistering and poor bond.
Acrylic membranes tend to be slow curing, as the skin on top and
underneath. Water based polyurethanes, SBR and Latex membranes are
faster curing
11. What is Wet Dry Film Thickness and why is it so important?
Knowing the solid content of liquid applied membranes allows applicators to
gauge the final dry film thickness membranes that are applied too thin will
compromise elongation properties and reduce resistance to abrasive damage
A large proportion of applicators continually apply liquid membranes too thin,
and then blame the product for failure. Liquid applied membranes rely on the
carrier, such as water or solvent, to evaporate leaving a final dry film. Wet film
membranes, therefore, contain a percentage of solids against carrier.
Most good quality water based membranes have a solid content of 50 to 66%.
A 60% solids water based membrane contains 60% polymer resin against 40%
water. When 1mm (1000 microns) of wet membrane film is applied, we are left
with 0.6mm (600 microns) as a dry film thickness(DFT). Water based
membranes with a higher solid content are normally rapid cure, and may split
64 or have their flexibility compromised when cured too quickly.
12. Commercial Trafficable Roof Top - Sydney
Image copyright @ Durotech
A good quality solvent based polyurethane
membrane has a solids content of above 70%.
Most are in the range of 75 to 85% solids. A PU
membrane with 80% solids and 20% solvent, will
cure to a DFT of 80% of wet film. When a
3mm(3000 micron) of trowel grade PU
membrane is applied, it will cure to a DFT of
2.4mm (2400 microns)
Knowing your membrane solids content and final
Dry Film Thickness (DFT) is critical in maintaining
the maximum potential performance of the
waterproofing system.
Measuring the membrane wet film, with a Wet
Film Gauge, will give an average measurement of
the wet coat and help to predict the final DFT.
13. Guide to Membrane Thickness
AREA Recommended DFT Application COATS
Lift pits 3 1.2 to 3mm
Basement 3 1.2 to 3mm
Retaining Walls 3 1.2 to 3mm
Podiums 3 1.2 to 3mm
Planter Box 3 1.2 to 3mm
Water feature 3 1.0 to 3mm
Wet area walls 2 to 3 0.6 to 1.0mm
Wet area floors 3 1.0 to 1.5mm
Balconies 3 1.2 to 2.0mm
Swimming pools 3 2.0 to 3mm
14. Class II
Silicone with No masking tape The liquid membrane will pool behind and
underneath the closed cell foam backing rod
if no tape is used.
Plastic 60% - 300% Elongation e.g. Acrylic membrane
How to install Bond breakers and fillets correctly and why is it
so important?
Type II Bond Breakers are typical with cementitious membranes and bandage reinforced membranes.
Reinforcement bandage can reduce a Class III membrane back to a Class II requiring a 35 mm bond breaker
system. This is usually achieved by 35mm of neutral cure silicone or a sacrificial tape, where the 35mm of
bandage releases from the substrate allowing independent membrane movement.
15. Class
III
Compatible sealant with concave
finish
Compatible sealant with a flat surface
Plastic 60% - 300% Elongation e.g. Polyurethane
Type III Bond Breakers are functional with lining systems such
as tiles or sheet cladding, where a gap of 3 to 5mm is
maintained at junctions
16. The risk of Moisture in your substrate and the problems it
can cause:
• The moisture content of the substrate should not
exceed 15% but may need to be even less
depending on what type of material you are
planning to use.
• The solid concrete floor is most often the slowest
part of the building to dry out.
• Commonly the concrete is coated or topped too
quickly or too soon causing the membrane to fail.
• A common system used in situations where
moisture is entrapped is epoxy primers. They help
seal a wet or damp floor from rising moisture
hence reducing bubbling of the membrane.
17. Image copyright @ Durotech
• Concrete is not the hard, dense, impermeable mass we
imagine it to be. It is a mineral /salt rich, porous material
full of tiny channels and voids. These pathways are just
right for the migration of fluids and vapours.
• Nearly all coatings lose bond strength, or simply will not
adhere at all, when applied to a damp, wet, or saturated
surface. How dry is your concrete surface you are
working on? Chances are it contains more moisture than
the coating manufacturer would recommend for
optimum adhesion.
• High moisture content will result in rising damp and salts
which will result in membrane failure through blistering
and pin holing. The application of a negative pressure
membrane over the substrate will control high moisture
and salts.
18. 1. No Bond breaker
2. Uncured membrane
3. Incompatibility of bond breaker and
membrane
4. Applied too thin
5. Applied too thick
6. Damage to membrane unseen pin
holes
7. Inadequate surface preparation
The main reasons why waterproofing fails and why it happens
19. Why waterproofing fails?
Image copyright @ Durotech
Either fill with neutral cure silicone as bond
breaker, and apply membrane or, install backing
rod and tape. Then bond breaker and apply
membrane. Bandage can be embedded in
membrane paint, left to dry and then return to
apply bond breaker and membrane. High Sheen
membrane the sealant is not cured must wait till
sealant is completely cured.
20. Why waterproofing fails?
Image copyright @ Durotech
• Uncured Membrane with entrapped dust and
dirt particles need to remove and re-apply
waterproofing.
• The membrane is too thin, we need to apply
more material if membrane is not applied to
the adequate thickness, the membrane will not
pass the manufacturer performance standards.
21. Image copyright @ Durotech
Why waterproofing fails?
• Membrane has split in corners as its been applied too
thick. Thixotropic products such as bitumen’s and
Cementitious membranes will split when applied
too thick. Must remove and re apply waterproofing
system.
• One pin hole can transfer through all membrane
layers as trapped air, as the cavity expands and pops
the drying top coat. Air must be expelled out of the
pin hole and then dress the paint over. Moisture in
substrate should be assessed and treated with the
correct negative pressure/ rising damp primer, such as
Epoxy primer or cementitious membrane.
22. Membran
e base
Type Flexibility Class Primer Connecto
r Sealant
Bond Breaker
/ Fillet
Uses & Characteristics
Water Base Acrylic
(Duromsatic
ACS)
Class III Water Based
(ARW
Primer)
FC
Polyurethane
MS Sealant
(Duroseal FC)
(Duroseal MS)
35mm N/C
Silicone
(Durosilicone
)
Internal / External above ground re-emulsify, slow dry, UV stable
Compatible with tiling/ render Apply above screed Apply below
bonded screed ONLY
WPU Class III
Water based
polyurethane
(Duromsatic P15)
Water Based
(ARW
Primer)
FC
Polyurethane
MS Sealant
(Duroseal FC)
(Duroseal MS)
12mm N/C
Silicone
(Durosilicone
)
Internal / External above Ground re-emsulsify, fast dry, UV
stable Compatible with tiling / render Apply above screed
Apply below bonded Screed ONLY
SBR Class III
Styrene Butadiene
Rubber
(Duromasti SBR Hybrid)
Water Based
(ARW
Primer)
MS Sealant
(Duroseal
FC)
(Duroseal
MS)
12mm N/C
Silicone
(Durosilicone
)
Internal / External above Ground re-emulsify, fast dry, UV
stable Compatible with tiling/ render Apply above screed
Apply below bonded screed ONLY
HIbuild Epoxy Class I
Primer (Duromsatic
WBE Epoxy)
Hydrate into damp porous
substrate
Rising damp/negative pressure limited activity window Sand
surface to reactivate Inflexible / does not resist abrasion Apply
above green screed or concrete Must cover with protective
coating.
Cemen
t
based
Neg Pressure Class I/II
(Durobuild Crystalline
WPM)
Hydrate into damp
porous substrate
Cement Fillet External Above & Below Ground Open
activity Inflexible / abrasive resistant
Apply above green screed or
concrete Must cover with protective
coating.
2 Part Class II
(Duroflex Tank)
Water based FC Polyurethane
(ARW Primer) (MS Sealant)
(Duroseal FC)
(Duroseal
MS)
35mm N/C
Silicone
(Durosilicone
)
External Above & Below Ground Open activity, full immersion Potable
water, resists rising damp Inflexible / abrasive
resistant Apply above green screen or concrete
Apply below unbonded screed
Liquid applied membranes fall into the following type of classifications:
23. Membran
e base
Type Flexibilit
y Class
Primer Connect
or
Sealant
Bond
Breaker /
Fillet
Uses & Characteristics
Solven
t
Based
Polyurethane Class III Solvent primer
(Hydro epoxy)
(Duroprime
PU)
Primer
(WBE Epoxy Primer)
FC
Polyurethane
(Duroseal FC)
FC
polyurethane
fillet 15 mm
(Duroseal FC)
Internal / External Above & Below High flexible Ground High
solids, abrasive resistant, Full immersion, very fast dry, Not
Compatible with tiling/ render Apply below unbonded screed
ONLY
Polyester resin Class I Solvent
primer Hydro
epoxy
FC
Polyurethane
(Duroseal FC)
75mm backing
rod + Vinyl
tape
Internal / External Above & Below Inflexible Ground High solids,
abrasive resistant Full immersion, Not Compatible with tiling /
render Apply below unbonded screed ONLY
Spirits Based Bitumenous Class
II (Duromsatic BLW)
Bitumen Paint
Bitumasti
c Neg Pressure cement based
(Durobuild Crystalline WPM)
Bitumastic
fillet Cement
fillet 15mm
External Below Ground Abrasive resistant
Full immersion, Root repellant Not Compatible with tiling /
render Apply below unbonded screed ONLY
Coal Tar Free Class
II Polyurethane
(Black Jack)
Bitumen Paint
Bitumasti
c Neg Pressure cement based
(Durobuild Crystalline WPM)
Bitumastic
fillet cement
15mm
External Below
Ground Abrasive
resistant
Full immersion, Root repellant
Not Compatible with tiling / render
Apply below unbonded screed
ONLY.
Bitumen Emulsion
Class II (Duromsatic
BLW)
Diluted Emulsion Bitumastic
(BLW
) Neg Pressure Cement based
(Durobuild Crystalline WPM)
Bitumastic
fillet Cement
fillet 15mm
External Below
Ground Abrasive
resistant
Full immersion, Root repellant
Not Compatible with tiling/
render
Apply below unbonded screed ONLY
24. Examples of projects where it is required to have waterproofing
Balcony & Entertainment Area- Grand Central Towers Image copyright @ Durotech
25. Examples of where it is required to have waterproofing
Podium Area - Grand Central Towers Image copyright @ Durotech
26. Image copyright @ Durotech
REQUIREMENT
Requirement was to have Hi-Quality – Eco friendly and Green star
rated waterproofing system in this 26 and 18 story twin complex with
no room for error. Designers and Engineers wanted an extensive
Diligence to be carried out prior to selecting The right Waterproofing
manufacturer and system. Product features and Accreditation were
critical aspect in the selection process. Furthermore a Proven and
tested history of waterproofing systems in similar developments.
Requirement was for a quick drying, flexible and Durable system
which was Eco friendly and Green star rated SYSTEM RECOMMENDED.
Proudly DUROTECH INDUSTRIES was approved as the preferred
supplier for all the wet area waterproofing requirements for the
development.
P15 system was used in internal undertile wet areas. A modified
acrylic urethane membrane. It has been formulated to create a
tenacious bond to most surfaces.
29. 1. To allow the membrane to stretch between adjoining surfaces.
2. To fill gaps, cracks and voids.
3. To provide the membrane with a material onto which it can achieve a
stronger bond
4. To provide greater water resistance properties to the system.
5. All of the above
What is the main purpose of a bond breaker?
30. Which of the following statements relating to primers are
true?
1. Only old substrates require priming.
2. Only the coving areas of a shower need to be primed.
3. The primer should always be dry before waterproofing.
4. Primers should be used to speed up the curing of concrete.
True / False
31. What is the main purpose of a Primer?
1. Toenhancethebondbetweensubstrateandwaterproofingmembrane
2. Usedasadampproofingcoatingtopreventwatermigration
3. Toactasawaterproofingmembrane.
4. Tohelpreduceandsealdustparticles.
32. What is the minimum “dry film thickness” which should be
achieved after two coat of a typical liquid membrane?
1. 0.3mm – 0.5mm
2. 1.0mm – 1.5mm
3. 0.5mm – 2.5mm
4. 2.5mm – 3.0mm
33. Which of the following a result in failure of waterproofing
system.
1. NoBondbreaker
2. Uncuredmembrane
3. Incompatibilityofbondbreakerandmembrane
4. Appliedtoothin
5. Appliedtoothick
6. Damagetomembraneunseenpinholes
7. Inadequatesurfacepreparation
8. Alloftheabove
34. What type of material are non-porous primers applied to?
1. Metal angles
2. Plastic angles
3. Flashing
4. Non - porous substrates
5. All of the above
35. What are some of the main points to consider when selecting
a membrane system?
1. The substrate type and moisture content
2. Flexibility Class
3. Root resistance
4. Ease of use
5. Toxicity (Safety)
6. One part or two part.
7. Bond breaker or fillet
8. Cost
9. All of the above
36. What is the best primer for James Hardy Skyon boards?
1. Epoxy Primer
2. Acrylic Primer
3. PU Primer
37. If a 60% solids waterproofing membrane is applied 1000
microns what is it DFT?
1. 800
2. 600
3. 400
38. What is the maximum moisture content of the substrates?
1. 5%
2. 20%
3. 15%
39. What is the reason a pin hole occurs in a waterproof coating?
1. Moisture?
2. Too Thick?
3. Too thin?
40. Gaps of up to 10mm between the bottom of the wall sheets
and shower recess floor can be filled in the following ways
(mark the boxes of all the correct answer).
1. Foam backing rods with masking tape.
2. Polyurethane Sealant
3. Polypropylene Reinforcing Fabric
4. Waterproofing membrane.
5. Any acrylic based sealant
6. Epoxy mortars
41. Waterproof membrane is ready to tile over when
1. Most of the flat surfaces (eg. The walls and floor) are touch dry.
2. The internal corners are only slightly damp.
3. The internal corners are all touch dry.
4. The membrane has fully cured on surfaces and in corner.
42. How much elongation does a class III waterproofing
membrane require to pass to Australian Standard?
1. Over >300%
2. Under <300%
Wet and dry film thickness
Knowing the solid content of liquid applied membranes allows applicators to gauge the final dry film thickness, and monitor compliance with manufacturer requirements. This is one of the more critical aspects of membrane application, as membranes that are applied too thin will compromise longation properties and reduce resistance to abrasive damage. This is one of the major concerns of all membrane manufacturers, where a large proportion of applicators continually apply liquid membranes too thin, and then blame the product for failure.
Liquid applied membranes will have both a dried state and a cured state. As with primers, an activity window may apply, where a solvent may be required to reactivate the membrane for subsequent coats.
Curing of water based membranes relies on evaporation of the water out of the membrane, leaving solid resin behind as a dry film. Curing is therefore dependent on ambient humidity, temperature and airflow. High humidity and low temperatures may slow membrane dry-out rates. Direct heat should never be applied to membranes while curing as it may result in blistering. Excessively hot substrates may cook the membrane, like an egg, and result in
blistering and poor bond.
Acrylic membranes tend to be slow curing, as the skin on top and underneath. Water based polyurethanes, SBR and Latex membranes are faster curing
Knowing the solid content of liquid applied membranes allows applicators to gauge the final dry film thickness membranes that are applied too thin will compromise elongation properties and reduce resistance to abrasive damage
A large proportion of applicators continually apply liquid membranes too thin, and then blame the product for failure. Liquid applied membranes rely on the carrier, such as water or solvent, to evaporate leaving a final dry film. Wet film membranes, therefore, contain a percentage of solids against carrier.
Most good quality water based membranes have a solid content of 50 to 66%. A 60% solids water based membrane contains 60% polymer resin against 40% water. When 1mm (1000 microns) of wet membrane film is applied, we are left with 0.6mm (600 microns) as a dry film thickness(DFT). Water based membranes with a higher solid content are normally rapid cure, and may split 64 or have their flexibility compromised when cured too quickly.
A good quality solvent based polyurethane membrane has a solids content of above 70%. Most are in the range of 75 to 85% solids. A PU membrane with 80% solids and 20% solvent, will cure to a DFT of 80% of wet film. When a 3mm(3000 micron) of trowel grade PU membrane is applied, it will cure to a DFT of 2.4mm (2400 microns)
Knowing your membrane solids content and final Dry Film Thickness (DFT) is critical in maintaining the maximum potential performance of the waterproofing system.
Measuring the membrane wet film, with a Wet Film Gauge, will give an average measurement of the wet coat and help to predict the final DFT.
Type II Bond Breakers are typical with cementitious membranes and bandage reinforced membranes. Reinforcement bandage can reduce a Class III membrane back to a Class II requiring a 35 mm bond breaker system. This is usually achieved by 35mm of neutral cure silicone or a sacrificial tape, where the 35mm of bandage releases from the substrate allowing independent membrane movement.
Nearly all coatings lose bond strength, or simply will not adhere at all, when applied to a damp, wet, or saturated surface. How dry is your concrete surface you are working on? Chances are it contains more moisture than the coating manufacturer would recommend for optimum adhesion.
High moisture content will result in rising damp and salts which will result in membrane failure through blistering and pin holing.The application of a negative pressure membrane over the substrate will control high moisture and salts.
Negative pressure membranes may allow continuation of the membrane application where otherwise minimum curing of screeds for 7 days may need to be observed. The application of such control membranes should be incorporated in all external applications, where porous substrates are present.
Moisture metre used to assess that the membrane has dried out sufficiently. Colour change, sheen and transference of colour onto a damp rag are other indicators. Membranes and primers may be dried in a number of hours, but not fully cured for water test or functional usage for a number of days.
Uncured Membrane with entrapped dust and dirt particles need to remove and re-apply waterproofing.
The membrane is too thin, we need to apply more material if membrane is not applied to the adequate thickness, the membrane will not pass the manufacturer performance standards.
Membrane has split in corners as its been applied too thick. Thixotropic products such as bitumen’s and Cementous membranes will split when applied too thick. Must remove and re apply waterproofing system.
One pin hole can transfer through all membrane layers as trapped air, as the cavity expands and pops the drying top coat. Air must be expelled out of the pin hole and then dress the paint over. Moisture in substrate should be assessed and treated with the correct negative pressure/ rising damp primer, such as Epoxy primer or cementitious membrane.