Ask The Trades - Print Page

Ask The Trades
https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Painting, Decorating & Tiling Questions >> Advice on Underfloor Heating https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1188725325 Message started by CadmannUK on Sep 2^nd, 2007, 10:28am

Title: Advice on Underfloor Heating
Post by CadmannUK on Sep 2^nd, 2007, 10:28am

Hi Guys,

I'm about to sort out our main bathroom in our bungalow. Its on the ground floor, concrete floor. I want to add under floor heating and have been looking at the electrical floor mat types. At the moment the wall and floor have had all their existing tiles removed and its basically back to bare plaster and concrete.

What would be the 'correct' procedure for laying these types of floor heating mats, types of adhesive, sealents to use etc etc. Someone has told me to use a rubber type adhesice on the floor and on the one wall with an internal stud construction?

Also what is the best way to get the floor sensor into the room?

On another subject, I want to tle travatine onto the wall and floor which is 10-12mm thick. Any advice on this part of the job would be great as well please.

Thanks

Cad

Title: Re: Advice on Underfloor Heating
Post by woodsmith on Sep 2^nd, 2007, 3:39pm

Unless you can add insulation under the heating mat I wouldn't bother. I fitted electric underfloor heating years ago and it's fantastic, trouble is it's on all the time and works out too costly to run.

I think since part P you need a sparks to do this work too. :(

Title: Re: Advice on Underfloor Heating
Post by jasonB on Sep 2^nd, 2007, 3:56pm

As keith says on a concrete floor its best to use a layer of insulation below the mat. This can be stuck to the screed with flexible tile adhesive. I've used the easy-heat insulation on the last few floors.

The sensor can be fitted into a groove cut in the insulation, best to fit it inside a small diameter conduit. I tend to use the Devi mat which comes with the conduit

Lay the mat onto the insulation then fix your stone onto this with a white flexible abhesive as grey can bleed through the stone. Seal the stone once laid then grout with flexible grout and seal again.

Wiring should be done by Part P qualified sparks and the mat should have RCD protection. Test the resistance of the mat throughout the installation to ensure it does not get damaged and don't switch on for 28days. Again as Keith says treat it as a way to take the chill of the floor not the only means of heating the room, a heated towel rail off the hot water circuit to the cylinder is the best bet here

Your stud wall will need a flexible white adhesive, masonary walls either flexi or solid. What is the wall surface you will be pushing the weight limit for skimmed walls with 12mm stone which is a flooring thickness, OK if its 10mm.

Jason