Insulating carpet underlay is it any good.

aylesby

We have a small bedroom which is over an integral garage and a kitchen. This room looses heat too quickly. We made the whole house warmer with full loft insulation recently but I am not keen on cavity wall insulation.
As we are decorating this room at the moment and there is a good carpet to refit. Is it worth changing the old carpet underlay which is 20 year old?
In B&Q I saw rolls of a metal foil backed contract underlay at £68 for 15 square meters. Has anyone used a product like this and did it make a difference?

brig001

We had this at our house and found the problem was caused by air leakage from the garage to the floor void (round cables and pipes) and air leakage past the joists from the cavity to the floor void. This void should be insulated and was only half done, so we topped it up with fibreglass. We took up the floor along the outside wall and sealed it all up and it has been fine since. To be honest, I don't think underlay will make much difference as it is too thin to have a significant insulation value compared to the 150mm of insulation that we fitted.

I think your options are in order of preference:
1, Do what I did.
2, Seal the garage from inside the garage and have cavity wall insulation fitted (this will reduce air leakage into the floor void).
3, While there is no carpet, seal the skirting board to the floor and seal any gaps in the floor (gaffer tape will do for this). Then get a good underlay.

We actually did all three to the whole house and knocked 40% off our winter gas bill while making the house warmer too.

HTH,
Bri.