British Gas free insulation - why not?

Dird

I signed up to the British Gas insulation review & will probably be called Tomorrow. If I'm part of the 90% that can apparently get the roof/cavity wall insulation for free is there any reason not to take it?

The seller mentioned the joint wall (semi-detached) having cavity wall insulation but I can't remember if she said the rest of the walls did.

Davesnave

Dird wrote: »

The seller mentioned the joint wall (semi-detached) having cavity wall insulation.....

Well, if it does, it would be a very rare thing! Party walls in semi-dees are hardly ever of cavity construction.

The point of a cavity wall is to separate the potentially wet exterior wall from the interior one.....and it doesn't rain much inside most houses.

The injection holes are usually visible unless really carefully hidden, but in any event BG will be able to check quickly.

Why not is a separate issue. There have been problems with CWI in exposed areas, but it's a case of DYOR as you know your house and the local microclimate.

Google 'CWI problems' etc.

http://www.which.co.uk/energy/creating-an-energy-saving-home/guides/cavity-wall-insulation/cavity-wall-insulation-damp-problems/

AlexMac

This is a great scheme, but it's not done by BG themselves, and some of the sub-contractors who do the work are unsurprisingly, only in it for the money (not to save the polar bears!) and in effect, more interested in their subsidised payment than ensuring appropriate treatment.

Case in point; we had 'em in and apart from smashing a glass lampshade next to the loft trap (which would have taken 5 seconds to unhook) they failed to tell me that they only insulated half the loft! So now we have two really toasty warm bedrooms (because their super thick loft insulation really works) and two really cold ones, because access to two loft areas was really difficult! So they missed that bit out; months passed before we realised this.

More worryingly, they also said I would benefit from cavity wall insulation but on examining my detached house said they couldn't do it because their regime reqauired access to all the walls, and one flank id only about 2' from the neighbour, so access was impossible. So I missed out on that, as they refused to do a partial job...

Thankfully- because when, a year or so later, we had a window fitted, the builder brother in law showed us the lovely thick mineral wool insulation which already completely filled the cavity and had been part of the original construction in the 1980's! So if the cowboys had come along and pumped some kind of foam gloop into the walls, it would probably have caused all sorts of problems.

I've also read about widespread problems of damp caused by retro-fit installation of filler into walls which lack vapour barriers as this screws the natural process of ventilation and breathing in older properties.

Finally- I did suggest to the stepson and his wife that they were wrong to allow the contractors to spoof them into a cavity wall job on the 100+ year old Victorian end of terrace, as I suspected they didn't have cavities to fill; whenever I've worked on my own Victorian homes the walls have been solid; you can sometimes tell by the brick pattern (search 'Flemish Bond'), but not always. They ignored me, went ahead, and I suspect all the contractor did was to drill holes, stick in a pump, switch on and let a load of foam fly all over the street (as the D-i-L said happened). Even worse, their skill in making good the pointing by the drill holes was useless- I saw the aftermath of snowball-like splodges all over the walls, sills and garden!

Read http://www.askjeff.co.uk/cavity-wall-fill/ - a caution by the Telegraph's very reliable 'house agony aunt'

G_M

http://www.which.co.uk/energy/creating-an-energy-saving-home/guides/cavity-wall-insulation/cavity-wall-insulation-damp-problems/

http://www.askjeff.co.uk/cavity-wall-fill/

http://www.freeinsulation.co.uk/articles/cavity-wall-insulation-problems.html

just google!

Dird

OK it matches with my initial assumption of avoiding cavity wall but accepting loft insulation (since nobody mentioned against this). Considering damp crept into the 3rd room last week I guess I'm not a good candidate for cavity