On Tue, 29 Mar 2005 22:56:59 +0100, "Doctor Evil"
wrote:


"Andy Hall" wrote in message
.. .


In order to calculate heat losses
and costs you have to look at all
the rooms and their expected
temperatures, not take them in isolation.

The idea is to put insulation in not size a heating system. The bedrooms
would greatly benefit by having 12" of insulation in the loft. (see above)


Never mind about the above. The original post was about putting in
some insulation and a heating system.

In order to do the second, the arithmetic on heat loss has to be done.
When it is, I would be willing to lay odds (and I never bet on
anything but 100% certainties) that the overall difference to the heat
loss will be negligible between using 150mm of insulation vs. 300mm
given the parameters of the house.




We are talking about heat loss *through* surfaces.

The point was air leakage. Please read back Lord Hall.

That was your point. Nobody else's.



The discussion was not about air tightness.
It makes some difference but not as much
as you imagine when ventilation is at the
recommended rate.

Air tightness is a part of it and you know nothing of it.

Air exchange is a normal part of living in a house and is accounted
for in normal heating calculations. There is no magic involved.




Not everybody wants to live
in a sealed box as you seem to advocate.

Another Lord Hall assumption. As
the Canadians say "Built Tight, Ventilate
Right"

We aren't in Canada

Do physics not apply over there?

Physics applies everywhere. The part that varies and what is
practicable and sensible depends highly on materials and method of
construction.

In this case we are talking about a house of over 150 years old with a
very restricted set of things that are going to be done to it. your
airtightness nonsense and superinsulation are completely irrelevent to
this.

The discussion is about house construction, not the bridge
construction with which you are more familiar.



--

..andy

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