"The Natural Philosopher" wrote in message
...
IMM wrote:

"Terry" wrote in message
. ..

Another problem that can arise with very high levels of insulation and
a
well sealed house, is large amounts of condensation.
In Scandinavian new builds I've seen this has been specially catered

for.


Well, sort of. But ..............
Here in Canada with longer colder winters (and often heat leaching
winds!)
higher values of the insulation reduce heat loss and therefore the cost
of
heating ones home. Since the energy cost increases of the 1970/80s etc.

much

thicker insulation has been the 'standard'. Most wood frame houses now

have

6 inch wooden stud outer walls filled with insulation and/or sheeted
with
foam boards, older homes 4 inch.
But it is the 'vapour barrier' on the warm side of the insulation,

whatever

type and thickness it is, that is important. It prevents the warm air
from
seeping out into the outer walls and ceilings. Warm air is moist; when
it
cools down the moisture in it condenses into water and can cause rot,

mould,

damp/wet insulation and even condensation and water droplets in the
attic.


It also makes the house air-tight reducing much heat loss in winter, and
gain in the summer. The Canadians have the R2000 standard, which is one
the
most advanced in the world, if not the most. The Canadians, say "build
tight, ventilate right".

Yes, but the whole point that you ALWAYS fail to realise is that cost
benefit analyse comes up with different answers for different climates.

In the Mediterranean and indeed in
most tropical places, its well known
that insulation is pretty useless unless
you also install air conditioning,

What codswallop!!! Look what they do in Florida.