In article ,
Skipweasel writes:
In article , says...
You will do better to make a huge double glazed south facing set of
windows, in terms of overall cost benefit, than anything else.

Passive solar gain can make quite a difference in the autumn and spring.
Since finishing the conservatory we've noticed we can do without the
heating until it's quite a bit colder outside (on sunny days) than we
could before. Opening the door allows the conservatory to heat the whole
house during the day and, with a sunlit concrete floor, for a couple of
hours after dark, too.

More attention to both desirable and undesirable solar gain in
house design would probably bear more fruit than many of the
pointless energy saving schemes which currently have the public
attention.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]