Description
Crommelin Shower Waterproofing Membrane is a ready-to-use, liquid-applied under-tile membrane for waterproofing showers and other wet areas before tiling, supplied here as a 1L pail for small jobs and repairs. It cures to a seamless, flexible waterproof layer with a textured surface that tile adhesive can grip, so you can tile straight over it.
About the formula
A water-based, heavy-duty, modified rubber membrane that is applied wet and dries into a continuous film with no joins to leak. The manufacturer describes it as permanently flexible with high elongation, with excellent adhesion to the substrate and a keyed finish that promotes direct tile adhesion. It complies with AS 3740 (Waterproofing of domestic wet areas) and is suitable for use with cement-based tile adhesives that conform to AS 2358. It can be applied either below or above a screed.
Where to use it
Indoors: showers, bathrooms, laundries, kitchens and wet rooms, on both walls and floors, under tiles.
Outdoors: balconies, under tile.
Suitable substrates include concrete and masonry, cement renders and screeds, plasterboard and wet area plasterboard, compressed fibre cement sheet (suitably prepared), timber, plywood sheeting, wet area particleboard and steel. It is not suitable for use over white-set plaster.
How to use it
- Prepare the surface so it is clean, dry, sound and free of dust, grease, curing compounds, release agents, loose particles, efflorescence and laitance. Concrete should have cured for at least 28 days, and screeds and renders for 7 days.
- Fill any holes or honeycombing with a suitable repair mortar and remove high points so the surface is even, with a light texture.
- If the substrate is not dry, prime it with Crommelin Dampstop. If the surface needs more consolidation, apply one coat of Crommelin Powerflex first.
- The product is ready to use. Stir it well, then apply with a 75mm or 100mm membrane brush or a 230mm membrane roller cover.
- Apply only when surface and air temperatures are between 10°C and 35°C.
- The manufacturer's recoat time is about 2 hours and the tile-over time is about 48 hours.
- Follow the Crommelin technical data sheet for detailing at corners, joints and penetrations.
Important notes
One litre produces about 1m² of finished membrane, which means building up the full film in the coats the technical data sheet specifies. Do not apply in conditions that are too hot or too cold. Make sure the substrate is properly cured and prepared before you start, because the membrane is only as good as the surface under it. For anything beyond a small area or minor repair, the 4L size may suit better. Check the current Crommelin data sheet for the full system and for the requirements that apply to your job.
Specifications
| Brand |
Crommelin |
| Product |
Shower Waterproofing Membrane |
| Pack |
1L pail |
| Colour |
Green |
| Base |
Water-based, modified rubber, liquid applied |
| Application |
Brush or roller |
| Coverage |
About 1m² of finished membrane per litre |
| Recoat time |
About 2 hours |
| Tile over |
About 48 hours |
| Application temperature |
10°C to 35°C |
| Standards |
Complies with AS 3740; compatible with cement-based tile adhesives to AS 2358 |
| Use |
Interior and exterior, under tile |
Safety
Use it with good general ventilation, avoid contact with skin and eyes, and wear suitable protective clothing. Do not let large spills reach drains or waterways. Store the pail in a cool, dry place out of reach of children. Refer to the Safety Data Sheet (SDS) for full details.
