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Jamie C · Joined: 16 Nov 2006 Posts: 68 Location: Essex

Our house which we are currently giving a fairly full makeover has a loft conversion that was built bout 30 years ago!

And this evening i decided to investigate the insulation in the stud walls as it seems noisy and hollow to me, and with the snow on the roof last winter you can see just how much heat was lost through our house roof compared to others in the street.

And no wonder, i chopped out some plasterboard tonight to have a look. Stud is 100mm deep, insulation is hanging there loosely and it looks like 50mm insulation has been used.

So, i need to reinsulate the walls, but on a budget.

So where is the best place to buy cavity insulation 100mm thick?

Im going with fibreglass insulation because its low budget.

Can I use a loft roll instead of cavity slabs?

On ebay 5.46m2 is £18.50, thats vs £40.32 for 6.55m2 at Travis Perkins!
And loft roll 100mm thick on ebay is £18.50 per 10.64m2 so even better VFM.

Any ideas, remember its low budget as we have run out of money to finish it all off!

Thanks, Jamie.

thescruff · Moderator Joined: 03 May 2003 Posts: 4662 Location: Bath

An 8 x 4 sheet of 50mm thick Celotex or similar from local builders merchant should cost around 20quid and is worth every penny.

I would buy what you can run too and do it in stages if neccessary, but buy the sheets and seal it across the the joists with tape to make a solid sheet.

Jamie C · Joined: 16 Nov 2006 Posts: 68 Location: Essex

Thanks, but gotta do it in a couple of days so cant buy a bit at a time.

Old plasterboard out, insualtion out, new insulation in and plasterboarded up, quick turnaround required.

Considering the rolls of fibreglass loft insualtion as the cheapest option. Any reasons for not doing that and using cavity slabs instead?

thescruff · Moderator Joined: 03 May 2003 Posts: 4662 Location: Bath

You get what you pay for in this case, Fibreglass and rockwool is indeed cheaper but not comparable to modern materials.

Personally I would wait a few months too replenish the piggy bank before starting on a second best job, insulation is very important and worth the best materials.

Jamie C · Joined: 16 Nov 2006 Posts: 68 Location: Essex

Scruff, point taken thanks, will spend the extra and do the job straightaway with celotex, funds will be pulled from elsewhere and something else will wait for time being.

Thanks, Jamie.

thescruff · Moderator Joined: 03 May 2003 Posts: 4662 Location: Bath

There is another make which is the same but much cheaper so work out how much you need and get a few prices first, you really can save a hundred quid plus by shopping around.

Cut the sheets with a sharp knife to fit tight between the joists/timbers, then use a foil tape to seal the sheet over the joist/timber to the next sheet, making an air tight wall.