Description
Crommelin Shower Waterproofing Membrane is a ready-to-use, water-based liquid membrane that waterproofs showers, bathrooms and other wet areas before tiling, supplied here in a 4L pail. It rolls or brushes on as a seamless, flexible layer and dries to a textured finish that tile adhesive can grip, so you can tile directly over it.
About the formula
A heavy duty, modified rubber membrane in a water-based, ready-to-use form with no mixing. Once cured it stays permanently flexible and stretches well, so it can cope with small movements in the substrate. It sticks well to suitable surfaces. The keyed surface works with cement-based tile adhesives, and Crommelin states it suits all cement-based adhesives that meet AS 2358. It complies with AS 3740 (waterproofing of wet areas). The 4L pail makes about 4 square metres of finished membrane, which is enough for a standard single shower recess.
Where to use it
Indoors: under-tile waterproofing of shower recesses and bathrooms, on both walls and floors, and in other internal wet areas such as laundries.
Outdoors: not specified by the manufacturer for this product. Check the Crommelin technical data sheet or contact Crommelin before using it on exposed external areas.
Suitable surfaces listed by the manufacturer include concrete and masonry. Check the current technical data sheet for the full list of approved substrates, and confirm that wet area fibre cement, plasterboard or similar sheeting is approved before you start.
How to use it
- Make sure the substrate is clean, sound and completely dry before you apply anything.
- Apply with a brush or a suitable membrane roller. Crommelin lists its Contractor Membrane Roller Cover as a compatible tool.
- At least 2 coats are required. Apply the second coat at 90 degrees to the first.
- Allow about 2 hours drying time between coats, as per the Crommelin how-to guide.
- Coverage is about 2 square metres per litre per coat. Complex or very irregular surfaces may need extra coats.
- Crommelin lists Dampstop, Reinforcing Fabric (with or without bond breaker), Polyurethane Sealant and Silicone WP Plus as compatible products for details and junctions.
- For a flood test, wait 48 hours, then pond water to a depth of 25mm for 2 hours. Remove the test water straight away afterwards.
- You can tile over the membrane after 48 hours.
- Clean tools and equipment with water before the membrane dries.
Important notes
Full cure takes 7 days. Do not apply to a damp substrate. Wet area waterproofing should be done to the requirements of AS 3740 and your local regulations, and many jurisdictions require a licensed waterproofer for the work. If in doubt, check before you start. This product is water-based, so keep the pail sealed and protect it from frost and extreme heat during storage.
Specifications
| Brand |
Crommelin |
| Product |
Shower Waterproofing Membrane |
| Size |
4L pail |
| Colour |
Green |
| Base |
Water-based, modified rubber |
| Application |
Brush or roller, 2 coats minimum |
| Coverage |
About 2 m² per litre per coat (about 4 m² finished membrane from 4L) |
| Recoat |
About 2 hours |
| Tile over / flood test |
After 48 hours |
| Full cure |
7 days |
| Standards |
Complies with AS 3740; suitable with cement-based tile adhesives to AS 2358 |
| Use |
Under-tile waterproofing of showers, bathrooms and wet areas, walls and floors |
| Clean up |
Water, before drying |
Safety
Avoid contact with eyes and skin, and wear gloves and eye protection when applying it. Make sure the area is well ventilated while you work and while it dries. Keep out of reach of children. If it gets in your eyes, rinse with plenty of water. Refer to the Safety Data Sheet (SDS) for full details.
