Cold single window dorma

[magnatom]

I have a single window gabled dormer which has just had its window replaced with a new double glazing unit. Despite replacing the DGing the area still feels cold. After taking to neighbours it would appear that the insulation around the dormer is not great.

I can get in to insulate some of the dormer through an internal access panel, however under the window and to the right of the window there is no access. I assume I could remove the plasterboard and insulate behind it, however, I'd like to keep disruption to a minimum (it's a kids room). Someone suggested that I could drill some holes through the plasterboard and put some expanding foam (fire retardant) through the holes to insulate it. Is this a reasonable thing to do?

 

[Nige F]

Not unreasonable yet not inexpensive for a number of cans

 

[magnatom]

Not unreasonable yet not inexpensive for a number of cans

True. It's not a huge area though, and it might be worth the expense to keep the disruption to a minimum. (My plastering skills are very minimal!)

 

[PrenticeBoyofDerry]

this will be a short fix solution, I hope when you have time in the future you remove a section of the pbs and insulate correctly.

 

[mointainwalker]

If you do that now, there is a high risk that the cold in the cavity will stop the foam from expanding at anything like its normal rate and it will remain rather thick and gloopy and fall to the bottom of the cavity.

The stuff I use says min 5 C when using but recently I estimate that instead of expanding 50 times as it says it should, at that temp it was more like 3 times.

If you cut the pb , insulate and then screw back the pb, surely your child isn't going to complain about the "damaged" decor.