On 31/01/2020 09:36, The Natural Philosopher wrote:
On 31/01/2020 08:59, Robin wrote:
On 31/01/2020 05:43, The Natural Philosopher wrote:
On 30/01/2020 18:07, Pancho wrote:
On 29/01/2020 10:10, The Natural Philosopher wrote:
On 28/01/2020 21:00, Robin wrote:
On 28/01/2020 18:33, Steve Walker wrote:

I would love to save money by saving energy, but physical
constraints rule out better insulation as an option - other than
replacing all the windows.


For our bedrooms I've pondered filling in the windows in (with
insulation), heat recovery vents through the ceiling, and flat
screen TVs on the inside with a live feed from external cameras to
see if it's raining etc.Â* But I feel there's likely to be problems
with the planners and over fire access

I've also pondered, given theÂ* thermal performance of even double
glazed windows,Â* putting to the Treasury the merits of a "window
tax".


You can add thermally interlined curtains and gain at least double
tethe double glazed performance


This is something I have wondered about. I have roller blinds, which
I figure would be quite effective, as there is an air gap. The fly
in the ointment of this theory is convection. I even drilled little
magnets into my window frames, so that the roller blinds snap shut
at the bottom. But there is still the sides and top, I think the top
is what pelmets were for?


But I guess convection would hurt thermally lined curtains too.

I've never seen any compelling research on this subject.

When I draw the big thermally lined curtains in my living room in the
mornings the wash of cold air on me bare tootsies suggests they do
more than a little.

Even though there are air gaps, they slow the rate of airflow down a
lot..

and they cut down radiative losses too.


Remember it's the base where the cold air wants to fall out. Not the
top.Normally the window cill is pretty much up against the lower part
of the curtain, and people who let theirs drape on the floor have
even more chance of trapping the air.


I agree that curtains can make a useful difference.Â* And that it's
important to try to create a layer of still air. Quantifying the
benefits is more problematic.Â* The little research I've read suggests
suggests it'd be a stretch to double the R value of even single glazed
windows.


Well my experience shows that it is a massive difference on single glazed.


One man's massive....

The most recent paper I've kept is at
http://usir.salford.ac.uk/id/eprint/42429/



--
Robin
reply-to address is (intended to be) valid