Biscuit screed between joists

[mutley racers]

Hi all. Hope you are well. I need to quote for a job where they want underfloor heating downstairs in the dining kitchen area. The dining room is screed and insulation. Old screed I have taken up and the old is suspended floor with 100mm joists with sleeper walls 350mm apart.

Anyone use a biscuit screed on these before or have you gone for aluminum plates? Looking for a kind of even heat output between the two rooms with warm up time etc.

 

[ShaunCorbs]

Or infill with insulation and ply and batton to top of joists and overlay the lot depending on height ?

 

[mutley racers]

Need the height to be the same as the screed finish which was flush with the floorboards. Not keen on biscuit screed shaun?

 

[ShaunCorbs]

No not for me if you infill the joists you can get 12mm or 18mm overlay which would be perfect and you can insulation and vapour barrier below

 

[mutley racers]

So your talking about putting 100mm insulation between, then overlay and then tiles on top of the overlay? When you say overlay, do you mean like osb with grooves in?

 

[ShaunCorbs]

100mm rockwool
vapour Barrier
Infill joists with 3x2 18mm down from top of joists
Install 18mm ply cut to width of joists fix to 3x2 with glue and screws

Then your concrete ufh panels can go straight across the top with no height build up

 

[mutley racers]

Thanks for helpful advice once again Shaun. Can you tell me which manufacturer you are referring to with the concrete overlay panels?

Cheers