Underfloor heating

[Yorkblade]

Hi,

We are extending our house and in the new section we will be having 100mm insulation, with 16mm pipes on top, covered with 100mm of screed.
However, the existing ground floor is suspended and I was wondering if someone could help.
I have seen diagrams where they have 50mm insulation inbetween the joists, board pipes, 25mm screed and then board on top again. Had anyone had this before when trying to use ufh on different floor build ups?

 

[Mr Chibs]

Can't comment on the suspended floor UFH, but don't think you want 100mm screed on the concrete floor, as it will takes ages to get warm. 60-75mm seems optimal. Liquid screeds can be slightly less, but are more expensive.

For suspended floors, check out spreader plates.
Polypipe do quite a good download showing all the options in it, might give you some ideas.

https://www.polypipeufh.com/support-hub/support-hub-downloads/

 

[Yorkblade]

Thank you.
So for the slab floor I was thinking.
125/150 hardcore
25 sand
DPM
125/150 concrete
100 insulation
Dpm or plastic sheeting
70 screed or concrete.

I was also thinking of changing he existing suspended floor to in the kitchen and dining room to match the floor make up of the new extended part (kitchen and dining to be opened up into new part.)
This removes the need to put in vent ducts and surely would be more economical with regards to the UFH