Waterproofing — Safe Work Method Statement

Waterproofing a bathroom or laundry is usually not High Risk Construction Work, so a SWMS is not legally required for that work alone, although most builders will ask for one. It becomes HRCW in two common situations. Balcony, podium, roof deck and external wall waterproofing often involves a fall of more than 2 metres from an unprotected edge. And applying solvent-based primers or membranes inside a basement, lift pit, tank or enclosed planter can create a flammable or harmful atmosphere, which is HRCW and may also make the space a confined space.

The main hazards are chemical. Many liquid membranes are water-based acrylics, but polyurethane, epoxy and bitumen systems can contain isocyanates, amine hardeners and solvents that cause skin sensitisation, occupational asthma, dizziness and fire risk. Get the SDS for every primer, membrane and sealant before you start and follow its ventilation and glove requirements. Once someone becomes sensitised to isocyanates or epoxy, even small later exposures can trigger a reaction, so skin and breathing protection matters on every job, not just big ones. Torch-on bitumen membranes add naked flame, hot bitumen burns and the risk of starting a fire in the substrate, roof space or adjacent materials, so they need hot-work controls and a fire watch.

Surface preparation also carries risk. Grinding concrete to remove laitance or old membrane creates silica dust, and old bathrooms may have asbestos cement sheet behind the tiles or under the floor. Membranes must be applied to the relevant standard (AS 3740 for domestic wet areas, AS 4654 for external above-ground membranes) and to the manufacturer's system, and some states license waterproofing as a separate trade, so check your state or territory regulator before quoting.

Customise this template with the membrane system and SDS references for every product, the area type (internal wet area, balcony, roof, below ground), how you will ventilate enclosed areas, the fall prevention for any edge, hot-work permit details for torch-on work, the asbestos status of existing substrates, and who signs off the flood test.