In article , PeterC
writes
On Sat, 18 Dec 2010 13:13:08 +0000, fred wrote:

1" of celotex might do the job in which case it could be stuck to the
underside and with a 45deg chamfer around the edge to half depth and
appropriate decorating finish it wouldn't look too obtrusive.

Now that's an idea that could work and it'd be out of harm's way when the
hatch is open.

I wondered if 1" would do so did a little calc:

If your hatch is the same size as the one you linked to it works out
about 15W loss for a 21degC diff (I assumed 18C for a hall and -3C in
the loft).

This from 0.77sqm door x U value of 0.95W/m2K for 25mm Celotex times
21degC diff.

Wallpaper/lining paper will stick to the foil on Celotex, I have done
something similar and mixed a little PVA into wallpaper paste to be
sure.
--
fred
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