Tile Surface Preparation Materials

(Source: Schluter-Ditra)
A few weeks ago I did a post on surface preparation. In it i pointed ou tthe importance of making sure that your surface is clean and prepared according to specification, and also making sure you use good materials.
One such material is Schluter-Ditra from Schluter Systems.
It is lightweight, and acts to both prevent cracking and waterproof the tile floor. Prevention of cracking is important but waterproofing is also vital to protect both wooden sub-flooring in wet environments.
Ditra also can reduce vapor pressure on the tiles above. Vapor pressure arises when moisture in your floor tries to diffuse into the room space above. This creates a pressure on the base of the tile which can cause it to pop up over time. Since Ditra is a plastic sheeting it acts as a barrier to the moisture thereby eliminating vapor pressure.