Waterproofing or wetsealing bathrooms and other wet areas is a very important preparatory stage of tiling that is sometimes not given enough attention.

There are two membranes used to waterproof. The first is the liquid membrane and the second is the fibre membrane.

Two or three coats of the liquid are applied. The fibre membrane is applied over the first liquid coat. The fibre is applied to the corners of the shower, along the floor corners and over any floor joins.

Care should be taken when fitting the membrane into the corners that no lumps are left. These lumps become quite hard and make the fitting of tiles very difficult. (The tiler has to grind the back of the tile to try to fit over the lump)

Also care should be taken that the liquid membrane is thoroughly applied so as not to leave even a pinhole. Water will find a way so one must not be left for it.