www.ultimatehandyman.co.uk

Hi guys,

Hoping for some help, have search around and got an idea may seeing what the guys in the know think.

Basically i'm looking to add electric UFH to a garage conversion. The garage floor has been raised to the rest of the house's level with a timber frame. Im planning on then finishing it with plyboard as tiles going on so steering clear of chipboard incase of cracks.

What is the best solution in order the develop this finish? If I insulated under the wood floor, do i still need insulation board above the wood, before the UHF, or can i lay the mate straight onto the floor, then use a flexi-adhesive to lay the tiles?

Hope you guys can help and thanks in advance....

I wouldnt put UFH directly onto any timber surface, the constant changes in temperature will cause movement and probably the tiles to crack/de-bond. I would fix min 18mm ply, screwed at max 300 c/s, then fix min 10mm insulation boards, then fix UFH cable, then cover in flexible levelling compound, then tile. The heating must be conditioned properly too. The more depth to the insulation, the better.

Thanks for the advice makes clear sense. Just one thing, would u bother with any insulation under the wood floor between the wood frame, aswell as the insulation boards?

Also hope doesn't sound silly, won't using the insulation board make the floor "soft"?

you will need insulation between joists on a timber frame floor..kingspan/celotex etc..100mm-150mm dependant on the thickness off joist..what have you got specced 150mm..175mm..??

just out off interst why electric and not "wet"..??

-- Wed Jul 21, 2010 1:51 am --

just to add..you will need insulation between the joist...this is mandotary sorry for bad sepellin lol..but it is under BC..

Rookery wrote:I wouldnt put UFH directly onto any timber surface, the constant changes in temperature will cause movement and probably the tiles to crack/de-bond. I would fix min 18mm ply, screwed at max 300 c/s, then fix min 10mm insulation boards, then fix UFH cable, then cover in flexible levelling compound, then tile. The heating must be conditioned properly too. The more depth to the insulation, the better.

Would be my choice too

Just remember OP, don't be tempted to turn your heating on until after about 4 week, then when you do don't crank it up but start at about 15 degrees and increase by 1 degree every 24 hours, once you have reached maximum temp then you can decrease to the required temp