How Much Does it Cost to Insulate a Loft/Attic (including a video introduction)
To have your loft insulated to a total thickness of 270mm, if you are over 70, or on certain government benefits, wish to take advantage of the grant and don’t live in a mansion
zilch, nada, rein, newt, nothing, it’s FREE!
To have it insulated under the grant scheme, even if you don’t qualify for a full grant, depending on the size of your property, you will pay between…
If you are above applying for a grant and decide to go it alone, assuming your loft is clear and your house is “normal size”. To add another 170mm of insulation to your existing 100mm will take 2 blokes half a day including buying the stuff…
170mm loft roll insulation £4.00 per square metre
200mm loft roll insulation £6.00 per square metre
150mm space blanket £7.50 per square metre
50mm Celotex PIR insulation board £10.00 per square metre
100mm Celotex PIR insulation board £16.00 per square metre
A Price Guide and Information Sheet on the Cost of Insulating a Loft
AND you can’t put “too much” up there. Today’s requirement (2010) for a brand new house with fibreglass rolls, is 270mm. That is usually achieved by laying 100mm between the joists and 170mm on top of the joists.
Ten years ago it was 200mm. In ten years time some new stuff will have been invented that leaves even the best stuff we have now (which you will be pleased to know, isn’t fibreglass) completely behind AND we will have to put 270mm of that down.
There’s a problem of course with putting a lot down, you can’t see the joist tops any more, so walking around up there is even more “hairy” than ever. If you lay down boards to walk on or store stuff, the insulation laid above the joists, squashes down. If you squash this 170mm down to 50mm say, you then only have a total 150mm of insulation.
It’s the trapped air, not the fibreglass, which does the insulating!
If you want to board out, make sure there is insulation, level with the tops of the joists, then deck out with proprietary, insulated boards (Celotex/Kingspan).
There are grants. Not just for your granny, for everyone but they won’t last forever. “Google” your way to a saving. There are plenty of companies, more than happy to “guide you through the process” then come and lay the insulation for you. All you have to do is clear the loft for them and you know, …..that might just be a good thing!