I
iamray
I am about to tile our new kitchen floor which has been extended and is concrete. Half of which does not have a damp proof course (the old bit), whereas the new half does.
The floor is in 3 sections; the old original floor is 3x3 metres, the new floor is 3x3 metres and a strip joining the two is 300mm x 3 metres. I'm concerned about damp rising through the old floor and delaminating the floor tiles and the levelling compound which I'm about to lay, also any potential for future movement cracking the grouting and tiles. The floor is relatively level but they are at slightly different heights (variants of 5-10mm).
When I removed some of the steel pipes that were buried in the old floor screed I had to pull up some of the old floor screed which is about 20mm in depth. This leaves me with a hollow in the floor surface which will also need to be filled.
My question is should I?
a) Use a mapei paintable damp proof course that's reinforced and use a floor levelling compound over the top of that with flexible grout and adhesive.
b) Paint the old section with a damp roof course and use a decoupling membrane and pour a thin screed of approximately 30mm (all I have to play with).
c) Go down a different course of action?
I've attached some pictures of the floor to help to explain my scenario
Many Thanks
Ray