DIY Doctor UK DIY Forums

Hi

I have bought a couple of insulated plasterboards (Knauf XPS Laminate Plus Insulated Plasterboard Tapered Edge) to go on a ground floor external wall that is cold and it cant be insulated externally.

I understand that on ground floors, you need to leave a 10-15mm gap between the bottom of plasterboard and the floor to avoid any damp or moisture rising up through the board.

My question is as I am trying to insulate a cold wall, do I just leave this gap of approx 10mm x 27mm hollow? I am worried about both heat escaping and also coldness coming through this gap.

I have seen in some places that people suggest using skirting board - whilst this visually covers the gap it doesnt quite deal with the issue of insulating that area.

Any reccomendations or suggestions? Is there a foam or other product I can use to fill to both fill the gap and that is moisture resistant?

Thanks

Hi azk
Probably the easiest solution is to use expanding foam which can be trimmed flush to the wall once set.
Regards S

I think expanding foam might have a similar issue to having the board level with the floor in that is may absorb or attract moisture which may work its way up the board and insulation

Hi ask
If you are concerned about water permability use a B2 foam.
Regards S

Hi ask
If you are concerned about water permeability use a B2 foam.
Regards S

Hi, did you try any PIR boards?
Regards,
Build4less

Hi, did you try any PIR boards?
Regards,
Build4less