Insulating the walls?

[darcymum]

I have recently moved to a new house, it is about 300 years old with thick stone walls and currently no heating. I have heard of some insulation you can put that is about 2 inch thick plasterboard that you put on the inside of external walls and then plaster over. Would this work well if we only did some walls in some of the rooms before then putting radiators in or would it be a waste of time and money?

Any help/ advice appreciated.

We did this in our 200 year old house. We did all the external walls. We also put masses of insulation in the roof when we re-roofed and replaced all the windows with new wooden, double glazed windows.

The house is absolutely toasty warm! I think it's the combined effect of all of our improvements, but the walls must be helping.

There is a building regs requirement that if you remove more than 25% of the plaster from any external wall, you have to insulate the walls before re-plastering.

Thanks for that, we moved in the middle of January and it was freezing! We plan to do the loft and windows as well. The walls are at least 12 inches thick and so dh doesn't think it will make much difference.

I don't know how thick our walls were - I'll ask dh when he wakes up.

Recently insulated some of external walls on our Edwardian house. Does help a bit. We also insulated below the floor boards as we replaced the joists. Does help.

A thin insulator can make a big difference if it has the right thermal qualities. For example a vaccuum 1 inch thick would probably be better than many insulators however thick? LOng time since I did A'level Physics. But it more bout Tog rating, i think.

Thanks for that, I think I will do some of the walls and get a dehumidifier. What do you think?

We battoned (not sure that is the right word) the walls before we put the insulated plaster board on so that there was an air gap between the wall and the plasterboard. Is that what you're talking about Tdiddy?

ye, an air gap is ideal. But even without airgap, it is worth insultaing regarless of how thick the wall is.