Insulating a wall

KeenToLearn · 2024-12-12T10:14:47+0000

Hi everyone,

I use my attic as a small stuff workshop- it is boarded and the rafters are covered internally in a couple of layers of double airtec and shiplap- has been like this for 20+ years and gets nice and warm up there with a heater on and is completely dry. I want to insulate the end wall- the brickwork is not flat so am thinking celotex not suitable therefore. So should I put fibreglass insulation against wall between battens, then vapour barrier on inside face of that then plasterboard or should I be using breathable roof felt? See so many conflicting ideas....

Thanks in advance for any advice you can offer.

Katomi woodsmith · 2024-12-12T10:18:48+0000

Banquet do a loft insulation that is made of plastic no nasty glass fibers
That and the vapour barrier then board it

KeenToLearn · 2024-12-12T10:40:07+0000

Katomi woodsmith said:
Banquet do a loft insulation that is made of plastic no nasty glass fibers
That and the vapour barrier then board it

Yes, I didnt mean fibreglass, I meant whatever the non itch type stuff is sorry.

MikeJhn · 2024-12-12T11:14:14+0000

What is on the other side of the end brick wall?

Ozi · 2024-12-12T11:36:09+0000

+1 for Banquet. Although I keep it away from electrical fittings in case there is a fire risk but so much nicer to work with.

ChaiLatte · 2024-12-12T11:49:37+0000

If you use mineral fibre insulation in a vertical application, you have to give some small thought to retaining it in place as it can sag. The Rockwool cavity insulation slabs are a little stiffer than the stuff that comes on a roll and can be cut generously and jammed in between studs.

If you are going to plasterboard it, the back of whatever the plasterboard screws to needs to be flat irrespective of how wonky the wall is. So just make the batten thickness at the most-projecting part of the wall equal to a celotex sheet thickness and then the celotex will work.