On Fri, 09 Feb 2007 19:53:57 GMT, a particular chimpanzee named luke58
randomly hit the keyboard and produced:

How do i check the effectiveness of a new double glazed installation.

I have had old aluminium units taken out and new UPVC units fitted.

But the house feels colder this winter, even as its milder.

What is the quality of the windows and their installation like? Are
there seals all the way around the glass, or are there gaps in the
corners? Do the opening windows close fully against the draught
seals? Are there cracks where the plaster meets the frame, or has it
been caulked? Externally, are there any gaps around the frame?

Do your new windows have trickle-vents where your old ones didn't?

If your old ali windows were more than a few[1] years old, they will
not have had a thermal break, so much heat will have been lost through
the frame. I cant see that a properly constructed and installed uPVC
frame could lose more heat.

Do you have central heating? If so, unless you've raised the
thermostats from last year, you won't be any warmer, you'll just use
less energy to maintain that temperature. Might it be your
perceptions? You could have been seduced by the sales talk that your
house would be much 'warmer' than before.

[1] 'A few' being a number, the value of which is unknown to me.
--
Hugo Nebula
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