Loft Insulation

[Endulini]

Hi All,

I am looking to get some insulation in my loft however the loft is fully boarded with nailed-down floorboards. I don't particularly want to go through the hassle of lifting them and then relaying them after and also a builder we got to quote reckoned that this wouldn't be a good way to go as the joists are quite shallow and banging around would probably disturb the ceilings. He also reckoned that as the current guidelines are for a 10 inch insulation layer we wouldn't be able to relay the boards anyway without compressing the insulation and compromising it. He advised us to either a) lay the insulation on top of the boards (but this would make the loft space unusable) or b) lay some other insulting material which can cope with some loft-boarding on top of it.

Does anyone out there know of these other types of insulation (he was a bit vague and I was a bit pushed for time by this point so didn't quiz him to vigorously) and what their relative merits/pitfalls are? Are there any other solutions bearing in mind we would like to use the loft space for storage etc?

Cheers

[Cicero]

================================== You might consider using polystyrene beads (about 6mm) which can be poured into cavities. You would need to drill suitable access holes but otherwise no other disturbance. Obviously, the depth would be limited by the overlaid flooring but it would be better than nothing.

would also need to avoid any wiring which can be degraded by polystyrene - plenty of dire warnings here from time to time.

Cic.

[John Rumm]

Any of the rigid PIR foam boards would be fine with a board of some description over the top. In fact you can actually buy the panels with a layer of ply already bonded to the insulation designed for building warm deck flat roofs.

If you look at any of the big name manufacturers sites like kingspan, ecotherm, celotex etc. they will have application notes showing these sorts of applications. The insulation performance of the boards is also far higher than rockwool or isowoool - so you won't need anything like the same thickness.

Prices are higher than for traditional loft insulation materials though.