Cavity Wall Insulation-good idea?

high-rise_andrew

think I can answer myself( am I turning schizo on here PMSL), it lookis like the dryline walls are boards to clad the inside of the walls & there is a lining of what looks like baking foil<to my eyes> so not a professional description. I'm on 3 benfits so will give them a call next week to see if I can have it done for free. wheeeeee.

topher_2

We've had cavity wall insulation installed about 3 months now. The 4th wall (its a detached house) can't be done due to access problems. The house was never really warm before and I can say thats the CWI has made a huge difference. Too soon to see how bills will be affected but I have turned the central heating down.

Ours was installed by http://www.millfold.co.uk/ - price was £150 but we had to pay £75 extra for roof access equipment.

mute_posting

tanith wrote: »

We would love to top up our loft insulation and a neighbour kindly gave us some he had left over but our loft is 3/4 boarded out , so it would mean unscrewing all the boards to put in more insulation and then the insulation would be too high for us to put the boards down again without compacting the insulation down.. defeating the object... any ideas how to get around this problem?

My brother solved this by laying new battens/"joists" perpendicular to the original joists/insulation and then topped up between these new joists before laying boards (which he'd wanted to do earlier but decided to lay the extra insulation and held off until he'd got around to putting the extra joists in)

kiwichick

I am very interested in having this done but need to ask a couple of dopey questions first!

1) Does it not make your house too hot in summer?

2) What is the difference between the types?

3) We bought a house with a loft conversion, will that make it harder?

4) What happens with the roof area?

Thanks Guys,
Al

moonrakerz

1. No. It keeps the heat out as well as it does in.
2. Foam or loose filling. Loose filling appears to be the most popular now - probably is easier to insert.
3. Not really, unless your cavity walls were extended upwards - unlikely.
4. Nothing. Get more lagging for that as a separate task.

johnllew

mute_posting wrote: »

My brother solved this by laying new battens/"joists" perpendicular to the original joists/insulation and then topped up between these new joists before laying boards (which he'd wanted to do earlier but decided to lay the extra insulation and held off until he'd got around to putting the extra joists in)

I'm interested in doing this. Could you tell me how he fixed the new joists to the old ones? Are there any brackets you can buy?

mute_posting

johnllew wrote: »

I'm interested in doing this. Could you tell me how he fixed the new joists to the old ones? Are there any brackets you can buy?

I'm pretty sure he just screwed through the sides of the new joists at 45 degrees, into the existing ones.

Personally, I'd avoid nailing as you might end up with cracks in your ceilings below.

I'm sure there are brackets, but (IMHO) these would be over-kill. The other option would be the perforated metal strip (about 20mm wide) they use for tieing roof trusses together, just cut some short (20cm?) lengths and put a twist in of 90 degrees and screw these to the new/existing joists.

HTH

MP

dogran_2

We had CWI installed about 3 years ago. As moonrakerz says, it actually keeps the house cool in summer, much more comfortable. During the winter preCWI we were sometimes having to turn the thermostats up & up but now its a lot better. I did feel cold spots in some parts of the rooms beforehand, but not anymore. It cost us £75 for a detached house, thats with some subsidy through the local council.
If you are planning on staying put for a few years, I'd suggest to get it done. Check with your council & on est website - grant search here http://www.energysavingtrust.org.uk/proxy/view/full/2019/grantsandofferssearch

WageSlave_3

Hi all. Useful thread but it's inspired a couple of questions the experts here might be able to answer...

Cold spots - am I right to assume these would be areas where the insulation isn't able to get to for one reason or another? Ie.e they remain uninstulated compared to the rest of the building.

Damp - I take it this is because air no longer circulates in the cavity and the insulation matterial allows damp to have direct contact with the internal walls and, thus, seep in?

Matterials - any ideas which is best? A local supplier uses foam but that doesn't seem to be favoured here. Also noted someone had wool but how on earth do they install that? In fact, how is installation done anyway? I've seen one site which seemed to suggest holes are drilled and they pump foam in but how are other better matterials installed?

Cheers in advance. I'm off to look at the sites suggested above!

Tribulation

We have a woodburner in our living room that used to be on every winter. We had two storage heaters in the front room (knocked through to dining room), but would still often be very cold.

3 or 4 years ago we had cavity wall insulation, since then we have never been cold enough to put the woodburner on. We have since got rid of one of the storage heaters and sometimes only need the other on 2 out of 3 days in the winter.

Very very worthwhile.

1930,s mid terraced house