I have an integral double garage that is already robbing the adjoining hall and room (and bedroom above) of lots of heat.
The external wall is cavity insulated, but the huge double door is a 60s metal up-and-over. This has to be the exit route of a lot of heat. I won't change the door - it's original and fantastically heavy with concrete counterweights - but I'm happy to insulate the back of it.
Googling hasn't really helped (I clearly don't know what I'm after), so any recommendations/tips?
Cheers

