Toppers

I was going to fit water fed UFH from a standard boiler, through a manifold with the pipes fitted between joists set on top of insulation in a biscuit screed mix - so far so good. I have then had that much conflicting information (loads of it) its totally put me off the idea and think of going for a double panel radiator with possibly an electric UFH mat to take the cold edge off the tiles. So frustrating.

It was from a company that supplies the UFH equipment, it would be better for them to advise me to use them as they sell them I'd have thought.

I was told the spreader plates dont conduct the heat as well as a biscuit screed mix so sort of steered clear of them. Yes the UFH is only in the this area/room.

We have a new suspended 6 x 2 joist floor and are planning to fit a water fed UFH heating system, I had set out the joists to allow for 18mm chipboard, 6mm tile backer, adhesive, tile to meet the level of the existing floor, would I be better going for a thinner ply and a thicker tile backer in order to make the UFH more effective?

Yes that could work I'm not that familiar with hardiebacker is it a fairly strong material?

Had a quick look and they only seem to do 12mm in hardiebacker I've already set the joists to accept 18mm chipboard (I'm matching up to an existing floor) so this could be a problem.

Do you think the heat will generate through the chipboard and tiles ok?

So to clarify on top of the biscuit mix do you have chipboard or is the oak straight to the joists? My construction will be biscuit mix, 18mm caber board, tile backer board, tiles.

I was talking to a heating engineer and he didn't rate the method above as being effective enough, has anyone any experience of installing/using this?

I'm ok with the floor and rads being on at the same time. Only one rad upstairs has a TMV at the moment.

I'm relocating a radiator in an adjacent room, pipework runs under the floor could that be utilised?

Would the manifold need connecting directly back to the boiler?

I've read/heard conflicting info so I thought I'd ask the questions on here, I'm planning on fitting a wet UFH system between joists on a suspended floor so in one room only (approx 23m2): What do the pipes need to be centred at Do I need a manifold or can it be connected using a TRV Does it need to be connected directly to the boiler

I think I'm going to stick with what I've started which is the pipework clipping directly to the top of the celotex 25mm below joist top.

Mine are C24 joists so I don't mind chiselling a notch out for the pipework to cross.

I was going for this method:

No I was going to leave the Celotex 25mm below the top of the joist and infill that with the biscuit mix. I assume this is the same difference.

I going to use standard 100mm Celotex and the 8:1 biscuit mix.

I'm using 6 x 2 joists which finish about 147mm, I've had some timber machined up to 22 x 22mm to give me 25mm at the top, I'll be using 16mm pipework. I'm putting the joists in over the next few days then the insulation to follow after the building inspector has been.

Yes I was going to do a similar thing with slate lathe and some 1 x 1 timber to let the insulation sit 25mm below the top of the joist.

I'm going to be putting UFH pipework on the top of 100mm Celotex insulation between joists, joists are at 400mm centres, how many runs of pipework would I need down each joist run? Length of each run is approx 5.3m.

Another alternative would be to span the joists the other way (approx 5.6m) and put a sleeper wall in the centre, do you think that would be a better option?

I was going to go 400mm centres as they are not in yet.

3.2m

Floor joists are 150 x 50mm.