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Hi
Trying to figure out UFH and Screed build up on Joisted floor in 1930s part of house
Going to Insulate between joists (wood fibre in 1930s area). Have (PIR in new Extension) seems to be no probs for any UFH make up.
But the 1930s joisted floor is making choice difficult
Wooden Floor boards mostly good but I have to take up anyway to insulate with Woodfibre board (fear of damp if I use PIR here)
If I want to put a Castellated system like Profix® PLUS Pipe in Flowing Screed should I reboard over the joists with :
ie Structural Deck
OSB3 Board
or
Renew/Reuse Wooden Floor Boards as flat as poss
Does it make a difference to Screed Depth what Structural Deck I use over the joists? I have been told 50mm ideally but the Profix Plus says I can use :
( 25mm is required for cement-based flowing screeds* or levelling compounds*, and just 30mm for anhydrite liquid screeds*)https://profixpanel.co.uk/profix-pl...reed-system-suspended-timber-separating-floor)
The other option PUG/DRY Mix with 25mm Battens onto Joists - UFH Pipes - Dry Mix Fill -TG No More Ply on Top for Structural Deck (hoping that board will conduct more heat than OSB). But I have had conflicting advice which way these should lie ie directly along the joists or across them (bearing in mind this will be the Structural Deck). Would the 25mm battens be in danger of twisting if too much weight on top?
Could also consider Insulated Cement based Panels and screed instead of all of above isn't poss.
Background:
Ground Floor 1930s Bungalow with soil solum, all is dry and no damp at present but I would like to stay away from chipboard in the older part of the house.
On top will be Porcelain Tile finish along with anti fracture mat.
UFH with ASHP
Heat Calcs have been done and all other areas insulated except 1930s floor.
Have UFH company but they are reluctant to make decisions about the underfloor. Although he does say that anything is fine so long as the Structural Deck is sound
Any feedback on the above would be welcome, thanks.
Trying to figure out UFH and Screed build up on Joisted floor in 1930s part of house
Going to Insulate between joists (wood fibre in 1930s area). Have (PIR in new Extension) seems to be no probs for any UFH make up.
But the 1930s joisted floor is making choice difficult
Wooden Floor boards mostly good but I have to take up anyway to insulate with Woodfibre board (fear of damp if I use PIR here)
If I want to put a Castellated system like Profix® PLUS Pipe in Flowing Screed should I reboard over the joists with :
ie Structural Deck
OSB3 Board
or
Renew/Reuse Wooden Floor Boards as flat as poss
Does it make a difference to Screed Depth what Structural Deck I use over the joists? I have been told 50mm ideally but the Profix Plus says I can use :
( 25mm is required for cement-based flowing screeds* or levelling compounds*, and just 30mm for anhydrite liquid screeds*)https://profixpanel.co.uk/profix-pl...reed-system-suspended-timber-separating-floor)
The other option PUG/DRY Mix with 25mm Battens onto Joists - UFH Pipes - Dry Mix Fill -TG No More Ply on Top for Structural Deck (hoping that board will conduct more heat than OSB). But I have had conflicting advice which way these should lie ie directly along the joists or across them (bearing in mind this will be the Structural Deck). Would the 25mm battens be in danger of twisting if too much weight on top?
Could also consider Insulated Cement based Panels and screed instead of all of above isn't poss.
Background:
Ground Floor 1930s Bungalow with soil solum, all is dry and no damp at present but I would like to stay away from chipboard in the older part of the house.
On top will be Porcelain Tile finish along with anti fracture mat.
UFH with ASHP
Heat Calcs have been done and all other areas insulated except 1930s floor.
Have UFH company but they are reluctant to make decisions about the underfloor. Although he does say that anything is fine so long as the Structural Deck is sound
Any feedback on the above would be welcome, thanks.