Waited 6 months for a company to come fit cavity wall insulation only to be told, on the day of insulation that the cavity is too narrow. Apparently the numbnuts that did the original survey didn't notice this fact.
Quite happy to believe them and not risk damp patches, but anyone know the alternatives? It's a 1950's house with loft insulation and double glazing, but it's damned difficult to heat in winter.

injection?

You can get internal or external insulative cladding fitted which will be a bit more hassle but is similarly effective. Bit of info here:

http://www.inca-ltd.org.uk/insulated-render-systems.htm

Matt_out and_about will probably be along soon to provide a lot more information than I can. 🙂

It's too narrow for the injection, apparently it may not spread properly so you get pockets of air which would be likely to cause damp.
Can't take the risk, therefore looking for alternatives really.

You can add external insulation, basically fix it to the outside of the house and then render over it.

I agree – you need to look at alternatives – pointless risking damp which would give you more problems with the house as well as making it feel cold anyway due to the additional moisture in the air.

HOw much loft insulation do you have?

6 inches at the moment with plans for 11 before winter.

Don't think the locals would go for external insulation, Bath's funny like that and the cost is somewhat large.

try silver bonded bead as I think they can fill smaller cavities

hard to find an installer, harder still to get one who will give you the subsidised installation, costs more but none of the problems associated with the rock wool stuff

I did it and noticed the difference

The local housing authority have just insulated the outsides of a load of their houses in my area. Basically they glued polystyrene to the outsides, then rendered over the top. Much to my annoyance they cut holes for the pikey's to get in & out.

I asked about the cost to do my house…nearly £9k.
I worked it out that it would pay for itself in about 80 years.

To save money I informed the mrs that from now on any polystyrene packaging would be glued to the outside of the house. It would look odd for a while but eventually I'd trim it all down to the same thickness.

There is a material, cant remember its real name but I think its known as "frozen smoke" or something like that. It came attached to plasterboard & gave the same insulation value as a styrene filled 8" cavity. Was expensive though, about £25/m^2 if I remember rightly.

How wide is the cavity – surely with 50mm you'd still be able to get injected fill, might just have to inject at much tighter centres than with a more modern 70mm cavity.

Living in Bath eh, you have my sympathies. You should do what they've done with the new shopping centre – rebuild your house with breezeblocks then cover it with a micron-thick layer of the local stone. 🙄

I understand that you can get insulative internal panelling, which might be an option if you can deal with making your house slightly smaller.

I worked it out that it would pay for itself in about 80 years.

You could offset the outlay with any grants that are going, and it would undoubtedly add a few quid to the value of your house.

If you use external insulation then it causes problems with the returns to the window and door openings, also with other "stuff" bolted on including RWPs and SVPs. Personally I think that overcladding mings.
Internal insulation is ok, but you will need to be aware that you lose floor area, and again the reveals to window openings is an area of concern as it could look oh, so wrong. One issue with internal insulation is that it reduces the temperature lag of heating/cooling the space – which may or may not be a problem for you.

Apparently they need over 50mm for injection and all the other forms of external or internal have just too many problems for not enough benefit.

Thanks for all the suggestions though folks.