Cavity wall insulation

[Lurkingforawhile]

Hi all. Prompted by being stuck in a very chilly house this winter I'm looking to make some improvements. I've found a good cavity wall company as many seem to be a bit dodgy, and I've just had an email back saying they're not doing cavity wall insulation at the moment. Most of the other recommended companies seem to be extracting rather than inserting cavity wall insulation. Am I missing something?

I do know we need to get some remedial work done to one wall first as it's not in good condition. Can anyone recommend a good installer in the South East. Thanks

I'm interested to hear the answer on this too. Cavity wall insulation seems to have fallen out of favour recently.

Housing Association homes around us ( Manchester) are all having CWI added, so not out of favour here!

We have it and constantly have flyers telling us we can have compensation if we get it removed?
It does make the house warmer in winter and unbearably hot in summer. We suspect that the damp patch in our hallway is caused by it, we’ll need to get it looked at after covid.

@Suzi888 that's really interesting as I thought insulation was supposed to help keep houses cool in summer. There are lots of companies who do removal now it seems

@EggysMom there's a govt scheme to pay for having it done but I just want to choose my own contractor and pay for it myself as I've heard some horror stories. Maybe all the contractors now work under the scheme

I wouldn’t get it done.
Cavity wall insulation goes in the whole cavity, even below the damp proof course. So when the insulation below the damp proof course gets wet, the water travels up through the insulation and through your interior walls.

I had it put in and it didn’t make the house warmer in winter and cooler in summer. What it did do was suddenly create a lot of condensation in the loft.
I wish I hadn’t bothered.

Thanks all. I think I might go for some other options instead and consider it a potential-bullet-dodged. Carpets with insulated underlay and a new front door also on the list.

There was a massive push in 1990's and 2000's to have cavity wall insulation installed with government grants. The previous owners of our large stone detached house refused as the DH was a surveyor and his mantra was yes it will reduce bills but in that era if house, they were not designed to have insulation that risked breaching the cavity. Some around us have had since very negative experiences and have had damp due to water breaching the cavity. I think it probably comes from a failure in pointing which wouldn't be immediately obvious but is when you get raging damp.

We have decided not to have it done and avoid having it taken out. There is a lot on forums about people suffering from it

Thanks @MarieG10. We have poor condition walls so that's a red flag for me. It's good to know about the concerns!

A reputable installer would refuse anyway if your wall were in poor condition - though as you have already said, not all are reputable. That said, if you are able to get the walls sound, cavity insulation may work well - the worst problems have been seen in wet parts of the country (wales etc). However there may be othermoves eg draghtproofing coupled with heat recovery ventilation, along with new doors etc, that might give a better all round result. The difficulty is finding someone well-enough qualified to give the best advice!

The house we used to rent had it and the corner of the wall in living room was permanently wet up to about 1m because the cwi was wet. Even in summer it never dried.

I should have said that our houses in a 1930s one and full of airbricks and lots of draughts!

Are you certain you actually have a cavity in the walls? Not all houses from that era do!

@candycane222 yes, I've checked with our neighbours and the survey report. A bit surprised to find out we have no insulation at all behind our hung tile wall though!

Yikes! That's going to be a bit parky! Sounds like a specialist job though...

If someone comes along and offers to fill the space with insulating foam run a mile!

If you are keen to get some good advice DM me, I can suggest a couple of places to try

Be very careful...

BBC - Cavity wall insulation 'a scandal',
www.bbc.co.uk/news/uk-wales-politics-39602540

@Lurkingforawhile it may do, we have a lot of glass and we are in an elevated position so the sun really shines in all through the afternoon and evening. It’s unbearable!
We’ve had people knocking door to door to offer removal, I’m quite worried about it. The house is much warmer in winter though. We don’t have the foam we have balls, they occasionally still pop out lol