I would think there are a lot of houses that dont have insulation!
Having just moved into a new (old) house, there is minimal insulation in the loft and the part of the house that has a cavity doesnt have insulation either.
Having looked into grants etc. If you happen to be married with no kids, both working. You get no grant at all or something stupid like £30 towards it.
Whereas if you sit at home claiming benefits popping out the muggers of the future.. you get the whole £3k+ paid for, loving new loft and cavity insulation installed while you sit infront of your large plasma TV watching Ricki Lake...nice
So unfortunately much as I would like to have insulation installed, save the planet and reduce my longer term costs of heating etc. I cant afford to as I'm paying all my taxes for others to have an easy life!
Only other option is for a 0% credit card which is the next step....