Tiling over wet UFH between joists - TilersForums.com

[CJ]

I need to quote for a job, as the title says........over wet UFH between joists. Much the same as the link I've put up.


Insulation, fitted between joists.....pipes laid, maybe with or without spreader plates. (Not sure as yet which way customer is doing this) then the floor would be overlaid with ply.....or maybe something else??? Then I mentioned putting down Ditra/Durabase.

Tiles they mentioned where 450x450 marble?? But not totally sure on that.

I have done this type of floor before, but some years ago and can't remember how I did it.

Any ideas?

 

[Chalker]

Forget the ply etc.
Just fit fermacell gypsum boards onto the joists. Prime and tile.
Make sure they have either used spreader plates or encased the pipe work with a solid mass.

 

[Dumbo]

Personally myself over board with 12mm ply making note of where pipes are then cross bond with 12mm ply glued and screwed at 150 centres then durabase and tile . Reason for ply is to add structure . Reason for two sheets no continuous joint from from joist to top then durabase for lateral movement .

 

[Old Mod]

Schluter will NOT guarantee an installation like this over ply.
As to other materials, I'm afraid I don't know.

 

[Kyle Knowles]

I laid 100m over this kinda system tjis time last year and had no issues as yet and that was 18mm ply over the pipes in trays with ditra then tiles with a s1 adhesive which isn't by the book but you all know what builders are like lol

 

[Kyle Knowles]

I wouldn't advise using 2 layers of 12mm ply it will take forever to heat up ....

 

[Kyle Knowles]

Hardi make hardifloor for this kinda installation

 

[Chalker]

Plywood will insulate. A solid mass is needed to transmit heat.
The primary function of ufh is to heat the room. any surface is just a decoration and should be able to transmit the heat too.
Thre should be a substrate that allows heat to pass through, does not suffer from large expansion and can support the weight that will be applied to the floor

 

[Dumbo]

Let's just bear in mind there are a lot of houses with wet under floor heating 22mm chipboard underlay and carpet . Yes I agree wood is an insulator and doesn't conduct heat as well as some other materials but it not as bad as some of you would make out . Oh and it works fine in my house and also through the engineered oak flooring .

 

[Chalker]

Let's just bear in mind there are a lot of houses with wet under floor heating 22mm chipboard underlay and carpet . Yes I agree wood is an insulator and doesn't conduct heat as well as some other materials but it not as bad as some of you would make out . Oh and it works fine in my house and also through the engineered oak flooring .

Yes it works, but not very efficient.