aluminium foil insulation

Like the rest of the country, I'm feeling the cold.

I'm trying to figure out the best way to insulate the loft rooms. Unfortunately the roof and ceiling are already in place, and taking them off to add insulation is not an option.

I do have access to the cavity in the rafters via the sides of the room, (storage areas), and I was thinking of trying to slide up some insulation between the rafters.

when I looked at the existing insulation I could only laugh. It's around 10 - 15mm styrofoam boards, so practically none then.

I did a little searching and came across aluminium foil insulation as a potential option.

does anyone have any suggestions or recommendations of these products, or even where to get them in ireland.

b & q supply 7.5m x 0.6 m rolls for EUR 55, so that's a start.

if you are installing the foil (which i dont consider a good idea) you need to removed the existing plasterboard anyway... so why not remove the plasterboard and install proper kingspan / xtratherm foam insulation??
Is this a dormer situation?

Multi layer foil insulation does not currently have an Irish Agrement Board Certificate. I would be a bit dubious of it's effectiveness. Also sliding something up along beteen the rafters - need to ensure that you have enough gaps left to allow for ventilation.

Thanks for that everyone.

I've had a look in the building suppliers at the xtratherm stuff. It looks pretty good,

I've got 110mm cavity between roof and plasterboard, with a 300mm span between rafters (old house), so the 70mm board is probably all I can fit in there.

It's not going to be ideal as I will not be able to fit the stuff snugly, more of a slide manouver from the bottom up, but it'll be better than what's there.

got a price for Xtratherm of EUR25 for 2.4m x 1.2m x 50mm from hardware store here in Galway. Does that seem reasonable?

cheers again.

deargas said:

Thanks for that everyone.

I've had a look in the building suppliers at the xtratherm stuff. It looks pretty good,

I've got 110mm cavity between roof and plasterboard, with a 300mm span between rafters (old house), so the 70mm board is probably all I can fit in there.

It's not going to be ideal as I will not be able to fit the stuff snugly, more of a slide manouver from the bottom up, but it'll be better than what's there.

got a price for Xtratherm of EUR25 for 2.4m x 1.2m x 50mm from hardware store here in Galway. Does that seem reasonable?

cheers again.

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I think you'd be wasting your time with this approach;
(a) you will not be able to get a snug fit of the xtratherm
(b) is it an A-frame roof? If so how do you propose to fit insulation at ceiling / collar level?
(c) sounds like a very frustrating job to try and achieve

I hear you, I know it's not an ideal situation, but I haven't got many options.

I don't have the budget to take down the ceiling (combination of wood panelling and plasterboard). I intend on raising the 2nd floor in a few years and the cost to do this in the interim would never be recouped in heat savings.

At the minute there's only 20mm styrofoam boards between the rafters.

We have sidepanels running the length of the house which give me access to the cavity in the rafters. (.75m from exterior wall). This will allow me to only have to cut the board in 2 sections in order to slide it right to the top of the roof.


I'm going to insulate the back of these side panels and in the cavity space between the rafters.

I'm working out costs of the insulation at around EUR300.