S
sparkyspike
I have a customer (I'm an electrician) who wishes to have an underfloor heating mat installed direct onto screed. The concrete floor is about 3" thick on top of jablite insulation. It will be tiled with natural slate.
Obviously I have advised that insulation boards are the best option, but they have a problem with matching threshold heights etc, so they want to avoid this. Plus, I think, the cost is a problem.
Topps Tiles recommended a 1mm waterproof mat under the heating mat, and they insist it does have thermal properties. I'm a bit skeptical about it though.
What I need advice on is whether laying direct on screed does dramatically increase warm-up times and running costs (so much so that it can't be done) and more importantly, affect the final temperature of the floor. A tiler once told me that tile adhesive is thermally conductive - more so than the screed - which is why a 100mm gap is normally left around the edge of a floor area.
I am happy to lay the mat onto the screed, unless I am advised otherwise. Any thoughts?
Obviously I have advised that insulation boards are the best option, but they have a problem with matching threshold heights etc, so they want to avoid this. Plus, I think, the cost is a problem.
Topps Tiles recommended a 1mm waterproof mat under the heating mat, and they insist it does have thermal properties. I'm a bit skeptical about it though.
What I need advice on is whether laying direct on screed does dramatically increase warm-up times and running costs (so much so that it can't be done) and more importantly, affect the final temperature of the floor. A tiler once told me that tile adhesive is thermally conductive - more so than the screed - which is why a 100mm gap is normally left around the edge of a floor area.
I am happy to lay the mat onto the screed, unless I am advised otherwise. Any thoughts?