Cavity wall insulation

rosscouk

Hi All,

I moved house a year ago and upgraded the heating system (oil). I have been insulating where I can to try to ensure the house is as economical as possible.

The loft was done in 09 and I have draft excluders and two new exterior doors to help. My house was built around 100 years ago and has had a couple of extensions. The last of which appears to be a cavity wall where by kitchen is and third bedroom (above). I don't think it has had cavity wall insulation and is quite cold most of the time. Therefore I was thinking of getting a Tesco's assessment prior to them carrying out the work.

Has anyone used Tesco's for cavity wall insulation? Should I get other quotes from local companies? How much should I pay? Is there any issues with damp I should be aware of?
Thanks for any help
Rossco

nickcc

If they charge as much for the insulation as they do for their kitchens I'd be looking for several quotes with other dedicated insulation providers.

Furts

How old are the extensions? If pre, say 1990, they would be unlikely to be insulated.

I assume there were no cavity wall guarantee paperwork when you purchased?

It would be a DIY job to drill from inside the rooms to check for any cavity wall insulation, then fill over and decorate.

I do not know current position with implementing The Green Deal. I throw this one out to fellow mse users.

LisaLou1982

no grants available for cwi on extension only. you would have to pay the full cost if u can find anyone to do it. and usually it has to be over 25m2 excluding Windows etc

you might be better with internal insulation

rosscouk

No, no cavity wall paperwork when we purchased the property although I think the extension was around 1990 era. From how cold it gets I would be surprised if it was insulated.

The extension is quite big, probably 35-45m2 without the windows so hopefully we could get it done. So, because of the size would no grant be available? How much might it be without?

Financewiz

Just a friendly warning - we purchased a house with it installed already and while the insulation certainly can improve heat retention, the chance of damp problems seems very high unless you have perfectly maintained brick/render exterior, a wall that meets every british standard going (and most don't) and do not live in a high rainfall/exposed house.

Energy Saving Trust does not recommend houses in exposed locations have it retro-fitted at all now.

We do, and the trouble trying to get CIGA (the 25-year government guarantee agency for cavity wall insulation) is amazing. They refuse to even acknowledge it could be an issue even when I have seen water dripping from the insulation with my own eyes and have proof of how much rubbish was already in the wall.

Google cavity + Jeff in the Telegraph and you'll see what I'm talking about. Worth doing your research!

rosscouk

Seems like I need to do some more research!!

I was worried about damp, however the house is not too bad now. Even if I didnt do the cavity walls and opted for internal insulation with either thermal plaster board or insulation wall-paper (or both) I suppose damp or mold would still be an issue. I do need to insulate the house further I am just not sure what is the next step.

Furts

rosscouk wrote: »

Seems like I need to do some more research!!

I was worried about damp, however the house is not too bad now. Even if I didnt do the cavity walls and opted for internal insulation with either thermal plaster board or insulation wall-paper (or both) I suppose damp or mold would still be an issue. I do need to insulate the house further I am just not sure what is the next step.

Be aware internal insulation will reduce your room sizes (maybe 60 -100mm on all walls), the products are expensive, fitting will be disruptive - think what happens at your window and door reveals, if your walls are not "true" you may need your new boards plaster skimmed after fixing. Finally you will need to redecorate.

These are some of the reasons why external cavity wall insulation has been the preferred option.

I trust this helps

rosscouk

So for internal insulation would it really knock 60-100mm off the room dimension? I have seen insulating wall paper and also the use of insulated plaster board over batons - has anyone had any experience with these? How were they and were there damp issues?

Furts

rosscouk wrote: »

So for internal insulation would it really knock 60-100mm off the room dimension? I have seen insulating wall paper and also the use of insulated plaster board over batons - has anyone had any experience with these? How were they and were there damp issues?

25mm insulation on plasterboard would be far from ideal. I would be looking for at least 40mm on plasterboard, and the more the better. This is not a cheap product and you only do it once.

Even plasterboard on 25mm battens gives you 37.5mm, hence 75mm reduction across the room.

As for insulated wallpaper,I would not entertain the notion.