Change old loft insulation?

[richsmith2005]

I've just moved into a property where it seems the loft insulation is way past its best. Since I'm spending so much on new windows and doors for relatively little enegery saving when compared to new loft insulation, is it worth having it done? The stuff looks to be less than 200mm thick and the loft is about as filthy as you can imagine, the insulation itself being the worst - absoluetly thick of dust and grime.

If I was to proceed, would I place the new insulation over the old, or first remove the old?

Many thanks in advance, Richard.

 

[JohnD]

If the roof is not felted then the loft will get very dirty again.

The insulation does not wear out so you don't need to remove the old.

If your insulation is thicker than the timbers are deep you will find it very difficult/unsafe to walk about up there. You might think about counterbattening it, then you have more room for insulation and can board it as well if you want. If the lay the extra insulation at right angles between the counterbattens it will also overcome most thin patches/joins/gaps.

 

[Sam026]

Also, try contacting your local council to see if there's a grant for supplying and fitting the new insulation. That's what i did 2 months ago and only cost me £99, job done.