On Fri, 23 Jan 2004 09:59:12 -0000, "David Moodie"
wrote:


"Dean Richard Benson" wrote in
message newsan.2004.01.22.17.24.49.501186@spamlessharker hill.co.uk...
On Thu, 22 Jan 2004 15:28:12 +0000, Andy Hall wrote:
That's exactly what I'm saying. Insulate it to the level of the walls
which is a U value of 0.25 to 0.35 for a place with cavity walls and
insulation. That equates to 100-150mm of glass fibre, not
350mm-600mm.

I think I am seeing your point.

On an older property, the U value of the walls can easily be 2.0.

Yep, my house is 250 years old, so really thick walls, but certainly no
cavity.

There is very little point in reducing the U value for the roof below
0.25 in the context of that.

Is there a way to find out the current heat loss through a wall?

Thanks

Dean

I was going to suggest the Knauf U value calculator normally available as a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the moment as it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you \re still
interpreted.

cheers

David


THe heatloss calculator programs from the radiator manufacturers have
this data as well....


..andy

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