We had double glazing fitted last week. We decided we needed it last year after Emma nearly put her foot through the rotten window frame in the front room while we were decorating.

It has definitely made a difference. We don't get a cold draught coming through the hallway at night. The back bedroom window isn't constantly covered in condensation. The bathroom seems warmer.

I know that double glazing isn't very cost effective. It may reduce heating bills, and it adds a small amount to the value of a house, but probably not enough to recoup the installation cost. It makes the house more comfortable, and that's what we're paying for really.