IS 9510:1980 is the Indian Standard (BIS) for membrane waterproofing in wet areas of buildings. This code provides guidance on the materials, design considerations, and workmanship for applying membrane waterproofing in building wet areas like bathrooms, kitchens, and balconies. It covers surface preparation, application techniques for membranes, and detailing at critical junctions to prevent water leakage. Note: This standard has been withdrawn, and current practice often relies on manufacturer specifications and the National Building Code (NBC).
Provides recommendations for membrane waterproofing of wet areas like bathrooms, toilets, and kitchens in buildings.
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Primary Recommended Materials | Bitumen felts, Hessian based felts, Plastic films (polythene), Bitumen mastic. | Liquid-applied membranes (LAMS), Sheet membranes, Cementitious waterproofing. Materials are performance-classified (e.g., Class I, II, III). | AS 3740:2021 |
| Membrane Upstand Height (General) | At least 150 mm. | At least 150 mm above finished floor level for walls enclosing a shower, 100mm for other walls in the room. | BS 5385-4:2015 |
| Membrane Upstand Height (In Shower) | 150 mm (no specific separate requirement for shower area). | 1800 mm minimum height from the finished floor level, or 150 mm above the shower rose if higher. | AS 3740:2021 |
| Wall/Floor Junction Treatment | Provide a cement mortar fillet (gola) with a minimum 20 mm radius. | A bond breaker system (tape or sealant) must be installed at the junction to accommodate movement. | AS 3740:2021 |
| Flood Test Duration | 48 hours at 25 mm depth. | Minimum 24 hours. Water level to be just below the termination height (e.g., doorway water stop). | TCNA Handbook |
| Sheet Membrane Lap | Not less than 100 mm for bitumen felts. | Minimum 50 mm, or as per manufacturer's specification. | AS 3740:2021 |
| Floor Fall/Slope to Drain | 1 in 48 to 1 in 60 is generally satisfactory. | Showers: Between 1:60 and 1:80. Other floors: Minimum 1:100. | AS 3740:2021 |