The substrate onto which the torch-on membrane system to be laid must be sufficiently rigid,dense and dimensionally stable to support the membrane system, insulation, surface protection. It must also be designed to incorporate the required falls,drains,sumps and outlets to ensure sufficient drainage, and have sufficient movement
Surface preparation:
No work should be started until all surfaces are clean,smooth and free of moisture and debris or any other substance that would prevent the membrane from adhering properly.
1. Make sure that plumbing, carpentry and other work is completed.
2. The roof must have a minimum slope 1%( 10mm per metre).the roof must slope evenly and continuously towards the drains.
3. There must be a gentle slope around the drain to avoid wrinkling of the membrane after it has been laid down.