Specification 26 Waterproofing and water-resistance requirements for building elements in wet areas

This Specification sets out requirements for building elements in wet areas that are required to be—

1. water resistant; or
2. waterproof.

(1) The requirements of this Specification apply to—

1. shower areas (enclosed and unenclosed); and
2. areas outside a shower area; and
3. areas adjacent to baths and spas; and
4. other areas as set out in clause S26C6.

(2) Where a shower is above a bath or spa, use requirements for a shower.

(1) For a shower area with a hob, step-down or level threshold, the following applies:

1. The floor of the shower area must be waterproof, including any hob or step-down; and
2. The walls of the shower area must be waterproof not less than 1800 mm above the floor substrate.
3. Wall junctions and joints within the shower area must be waterproof.
4. Wall/floor junctions within the shower area must be waterproof.
5. Penetrations within the shower area must be waterproof.

(2) A shower with a preformed shower base must also comply with the requirements of (1), except for (a) which is not applicable.

(1) For concrete, compressed fibre-cement and fibre-cement sheet flooring, the floor of the room must be water resistant.

(2) For timber floors including particleboard, plywood and other timber based flooring materials, the floor of the room must be waterproof.

(3) Wall/floor junctions must be waterproof.

(1) For areas adjacent to a bath and spa, the following applies:

1. For concrete, compressed fibre-cement and fibre-cement sheet flooring, the floor of the room must be water resistant.
2. For timber floors including particleboard, plywood and other timber based flooring materials, the floor of the room must be waterproof.
3. Tap and spout penetrations must be waterproof where they occur in horizontal surfaces.

(2) For areas adjacent to a non-freestanding bath and spa, the following applies:

1. Walls must be water resistant—
   1. to a height of not less than 150 mm above the vessel, for the extent of the vessel, where the vessel is within 75 mm of a wall; and
   2. at all exposed surfaces below vessel lip.
2. Wall junctions and joints must be water resistant within 150 mm above a vessel for the extent of the vessel.
3. Wall/floor junctions must be waterproof for the extent of the vessel.

(3) For inserted baths and spas, the following applies:

1. For floors and horizontal surfaces:
   1. Any shelf area adjoining the bath or spa must be waterproof and include a waterstop under the vessel lip.
   2. There are no requirements for the floor under a bath or spa.
2. For walls:
   1. Waterproof to not less than 150 mm above the lip of a bath or spa.
   2. There are no requirements for walls beneath the lip of a bath or spa.
3. For wall junctions and joints:
   1. Waterproof junctions within 150 mm of a bath or spa.
   2. There are no requirements for junctions and joints in walls beneath the lip of a bath or spa.
4. Tap and spout penetrations must be waterproof where they occur in horizontal surfaces.

(1) For walls adjoining other types of vessels (e.g. sink, basin or laundry tub), the following applies:

1. Walls must be water resistant to a height of not less than 150 mm above the vessel, for the extent of the vessel, where the vessel is within 75 mm of a wall.
2. Waterproof wall junctions where a vessel is fixed to a wall.
3. Waterproof tap and spout penetrations where they occur in surfaces required to be waterproof or water resistant.

(2) For laundries and WCs, other than WCs as described in (3), the following applies:

1. Water resistant floor of the room.
2. Water resistant wall/floor junctions.
3. Waterproof penetrations where they occur in surfaces required to be waterproof.

(3) For WCs with a handheld bidet spray installation, the following applies:

1. Waterproof floor of the room.
2. Walls must be—
   1. waterproof within a 1500 mm radius from the wall connection of the handheld bidet spray device to a height of not less than 150 mm above the floor substrate; and
   2. water resistant within a 1500 mm radius from the wall connection of the handheld bidet spray device to a height of not less than 1200 mm above the finished floor level of the WC.
3. Waterproof wall junctions within the WC area within 1500 mm radius from the wall connection of the handheld bidet spray device.
4. Waterproof wall/floor junctions within the WC area within 1500 mm radius from the wall connection of the handheld bidet spray device.
5. Waterproof penetrations in WC area.

(4) For bathrooms and laundries required to be provided with a floor waste by F2D4, the following applies:

1. Waterproof floor of the room.
2. Waterproof wall/floor junctions.
3. Waterproof penetrations where they occur through the floor.