Sub Floor Design For planned Under Floor Heating

[anonymous-user]

The initial message was deleted from this topic on 27 February 2025 at 17:15

[PhilboSE]

From bottom up:

Subfloor (to spec; MOT & sand blinding)
DPM
Slab
DPM
Insulation
UFH pipes
Screed on top

Using separate contractors is going to add friction to the process as you will be mid-build and the primary never likes having secondaries floating around if he’s not subbing them. They will blame each other for inconvenience and delays and any resultant issues. There are also liability and insurance issues for site safety.

Installing UFH is pretty standard and simple - why aren’t you trusting the main contractor to do it?

Also make 100% sure that everyone knows the final floor levels and works to them. If there’s any misunderstanding they will all blame each other and duck fixing the issue at their cost.

Edited by PhilboSE on Saturday 13th August 11:46

[Equus]

PhilboSE said:

From bottom up:

Subfloor (to spec; MOT & sand blinding)
DPM
Slab
DPM
Insulation
UFH pipes
Screed on top

Nearly right: the second DPM is a 'separation layer', and it goes between the insulation and the screed, not between the insualtion and the slab: