"Dean Richard Benson" wrote in
message newsan.2004.01.21.18.28.06.252332@spamlessharker hill.co.uk...
On Wed, 21 Jan 2004 16:29:12 +0000, Christian McArdle wrote:

Yes. The law of diminishing returns says that 350mm is the best
environmentally speaking. Any more and the environmental cost of
manufacturing and transporting the insulant is higher than the energy
saved.
100mm is definitely on the low side. 200mm would be better. The
difference
between 200mm and 350mm isn't that great.

Some useful info in there. Leads me to even more questions....

- with currently having a 100mm joist height, should i either increase the
joist height (cross joists) or just cross-lay the insulation over the top
of the 100mm.

- If you insulation up to 350mm, how are you meant to ever reach places in
your loft without falling through the ceiling ;P


The problem is that with a 100mm joist height you aren't meant to store
anything, other than insulation in your lost. Its one of those cases where
the builders use the absolute minimum they can get away in order to save a
few quid and you end up with some valuable storage space that you
effectively can't use!

cheers

David