Retro Insulation for Flat roof-Pumped?

redman

Hope someone on here can give me some advice.

I have an extension to the house that has a flat roof.However, it would seem there is non existent insulation in the gap between the ceiling and roof, between the joists.
It badly needs insulation as the heat just flows out of the room.

The roof will need replacing in a few years but I am maintaining it to keep it lasting as long as possible. Also I could remove all the plasterboard on the ceiling and place in insulation but messy and costly.

Is it possible to get someone to pump some form of insulation between this area? Any recommendations?

Thanks for all advice
Redman

MicktheMan

Why will the roof need to be replaced in a few years or do you mean the roof covering?
I would strongly advise you NOT to have the gap between the joists pumped with insulation as the timbers need to be ventilated, otherwise they will rot in no time. I afraid that your only option is to remove the ceiling slab and apply insulation to no more than half the joist depth on the room side. The joists themselves can then be insulated by applying insulation between the joists and the new slab board if headroom permits.

redman

MicktheMan wrote: »

Why will the roof need to be replaced in a few years or do you mean the roof covering?.

Sorry yes I meant the covering!

MicktheMan wrote: »

I would strongly advise you NOT to have the gap between the joists pumped with insulation as the timbers need to be ventilated, otherwise they will rot in no time. .

Very good point , I hadn't considered that!

MicktheMan wrote: »

I afraid that your only option is to remove the ceiling slab and apply insulation to no more than half the joist depth on the room side. The joists themselves can then be insulated by applying insulation between the joists and the new slab board if headroom permits.

Well thanks for that advice , much appreciated.

Is there such a thing as a slab board with some thin insulation built in that one could simply screw onto the existing boards (losing some headroom)?

Builderfromhell

I'd have to agree with 'Micktheman'.
It should not costa fortune to take down ceiling board and replace with foil backed plasterboard.
Insulated plasterboard seems like a good idea but very difficult to install due to their weight. Also, they could pull through screw heads and collapse into room.

redman

thanks