Tiling in Shower Recesses
The minimum standard required for wet areas in residential buildings is contained in the Building Code of Australia (BCA) and AS3740 – Waterproofing of wet areas in residential buildings. This includes tiling and gradients of bathroom floors including shower recesses.
The recommended ratio of fall within showers is between 1:60 and 1:80. However, the ratios may not be achieved due to:
(a) The size of the tiles used – falls become more difficult to achieve with larger tiles.
(b) The area of the flool to be drained.
In these cases, the effectiveness of the floor drainage should be measured by the performance of the floor. If water does not remain on the finished floor in a manner that can adversely affect the health or amenity of the building occupants or deteriorate building elements it may be deemed adequate.
Discuss your concerns with your builder with these factors in mind.