Loft insulation rolls for 60mm deep joists?

NewtoDIY

Sorry if this has already been covered on here ( I couldn't find a reference so far), but does anyone know of any companies that sell loft insulation rolls to fit 60mm deep joists? They're also 600mm wide. I've been looking online and can find everything above 100mm for thickness but no 60mm rolls.
Thanks in advance

fluffymuffy

That's because insulation needs to be thicker than that, - you need about 250mm to meet today's building regulations.

Why not just buy the thick stuff and have it sticking up?

NewtoDIY

I know that, but I want to use an additional level of rigid insulation going across the joists and then use as storage. It's an old house hence the 60mm depth joists.

leveller2911

NewtoDIY wrote: »

I know that, but I want to use an additional level of rigid insulation going across the joists and then use as storage. It's an old house hence the 60mm depth joists.

You can use rigid insulation (celotex,etc) 50mm thick and cut it in between the joists.

IIRC an inch of Celotex is equel to 100mm of rockwool,fibreglass insulation. Then Celotex 90 degrees over the joists.. 100mm of Celotex = 400mm of fibreglass etc...Cost would be pretty high though as Celotex isn't cheap.

MX5huggy

leveller2911 wrote: »

You can use rigid insulation (celotex,etc) 50mm thick and cut it in between the joists.

IIRC an inch of Celotex is equel to 100mm of rockwool,fibreglass insulation. Then Celotex 90 degrees over the joists.. 100mm of Celotex = 400mm of fibreglass etc...Cost would be pretty high though as Celotex isn't cheap.

Celotex is not that good, it's about twice as good not four times.

Just put 100mm between the joists and what every you had planned over the top. The 40mm by 40mm still air gaps won't be that bad.