Concrete Floor.

[buildersbutt]

Hi all, have a timber floor which is rotten, laid on a concrete sub base which appears to be solid, they have laid 3"x 2" timbers flat with chipboard on top and then tiled. Want to replace wooden floor with extra DPM, insulation and a screed over the top. I know that the 2" insulation should be under the concrete, but we only have 4" to play with and don't really want to break old concrete up as it is solid. Any ideas on this apart from doing what I don't want to do, the room is 8' x 8'. Thanks for your time.

 

[noseall]

What you are suggesting refers to an un-bonded floor.

I would only be comfortable with a screed thickness of 75mm or greater in this situation.

However there is nothing to suggest that a stronger/harder 50mm screed on say 50mm celotex with 1200 gauge polythene will not be a success.

What caused the original floor to rot?

 

[buildersbutt]

Hi noseall, the problem is two fold, firstly there was a leak under the bath and secondly there was no air vents under the floor, so under bath wet rot, rest of room dry rot. Was thinking of claiming off insurance but would they want to know as the job wasn't done properly in the first place before we bought the property, if we could claim would it be better to replace new timber floor on sub base with air bricks, as we don't have much room for insulation and screed. Thanks for your time.