Insulating a cold extension

[beatricequimby]

We have a big kitchen diner extension that was built in the 1970s. It is much colder than the rest of the house and I would love to do something about it but I don't know what is possible. We have put in bigger radiators and re-roofed with much roof insulation but is there anything we can do to the walls?

If you have loft insulation to the current standard of 270mm mi eral wool, look next at the walls. They are most likely cavity so you have CWI. You say extension so it should be much better insulated than a conservatory.

Does it have a lot of glass?

What sort of floor does it have?

...so you Could have CWI.

Piglet John -thanks

It doesn't have a lot of glass. French doors and a window but mostly just external walls.

I was thinking of CWI but a friend had it done and said it hadn't made a lot of difference. But maybe hers wasn't done very well.

Is it something you would usually recommend?

I have been very pleased with mine, and the wool is water-repellent so does not hold damp.

the contraindications are faulty walls with cracks, gaps, bad pointing, loose render that can cause rain penetration, or exposed locations suffering from driving rain against the wall.

I am in an exposed coastal location, but the wall facing the incoming weather is tile hung to keep the water off. The other walls are exposed brick but do not get wet. The installers are supposed to inspect your walls for possible problems, and if a problem occurs that they cannot cure, can be forced to remove the fill. If you are thinking about it, try to have the whole house done. I had mine done by BG who I knew would not go bust or fail to honour their guarantee, they were very quick and clean.

Piglet John - Thanks that is really helpful. I don't think my house has any of the contraindications so will look at getting some quotes. Will let you if we get it done!