Water proofing is the process of protecting the wet areas in your house from water damage. Areas that will need waterproofing include the bathroom and shower area. Watre proofing prevents the water from getting into the rest of the house and containing it to the area you want wet only. Without water proofing water would get into the timber and other structural components of the house and cause damage.
Once the surfaces are prepared a membrane is put down which acts as a barrier to the water. This membrane is sealed in place with a sealant and allowed to set.