Hi

[Preamble, Questions at end]

We're going to move in with my Dad next year - we're redoing bits of the
dormer loft conversion of his bungalow.

Now, upon inspection, the current insulation in the roof voids is manky
glass wool - yuk. Broken, falling away and very dusty.

I hate glass wool, partly as I a) have to get around the voids to fix some
electrics + install networking, and b) I'm going to use the voids as
supplimentary storage space for light items. I find it unpleasant and
a skin irritant. I also don't want the fibers going anywhere near my
baby daughter. Also, it's too knackered to be doing much good.

I also want to insulate the roof, not the floor as I want the voids to run
warm to protect the stuff I'm storing.

So I thought about using either Celotex/Kingspan to 50mm, leaving 50mm
breathing space in the rafters under the tiles - or rockwool slabs.

Rockwool in slab form is possibly less disgusting than glass wool
- at least once fitted (anyone care to comment?) but I believe from
reading around I'll get better insulation with Celotex or it's like at
50mm.

[Questions]

a) What's celotex like to cut - use a knife or a saw?

b) In a fire, does it pose any risk of giving off noxious fumes?

c) Does having an endothermic but still combustible material like
celotex packed around electric cables bother you?

Thanking you kindly :-)

Timbo

--
Tim Southerwood
Website: http://www.dionic.net/