External wall insulation

[Giggorata]

Has anyone got any long term experience of external wall insulation?
I am interested in how it performs over a longer period re heating bills reduction, house temperature differences, durability, cost and maintenance needs (if any)
I have a large cold period house! I'm not sure I could afford the whole house to be done, so I'm also wondering if I could just get the back done, for example, or if you always have to do the whole house.
I’ve done a bit of Googling, but I'm really interested in first hand accounts from unbiased Mumsnetters.

Placemarking as we plan to do EWI.

oreste, do you have the room for internal wall insulation? It reduces the room size.

The rooms are biggish Victorian with alcoves. Nobody wants to give up internal space but I am debating which of the two would be the lesser of two evils. 😐EWI gets recommended as being superior if slightly more expensive. I don't really like the idea of ruining a lovely old brick wall with render (even though it may cover the odd crack) . Brick slips are probably too expensive for my size of property.

Ah, gotcha.

we will have to do some brick slips as we are in a conservation area and the brick is part of the character. But much of the wall is lime plaster and we can put textured EWI that looks similar over that.

(We have a “skirt” of brick about 2 ft high to reproduce with slips)

I actually dislike the idea of these products (they sound like fake textures you would find at a theme park) but only slightly less than freezing. I literally get chilblains indoors every winter! I am driven to consider it through desperation 🙁

I think 60mm would be fine.

If you're building a new house, designed from scratch, 100mm is better, though you get diminishing returns, but I think awkward to add to an old house.

BTW foam has about double the insulating power as the same thickness of mineral wool.

Thanks a lot. I am definitely not installing it on the facade after all the effort I took to restore it. Mainly along the massive side elevation. I'm also not sure whether I can leave out the wall with the pipework as that is where many issues arise as I understand it. Is it really all-or-nothing or can you mix and match IWI and EWI? Would it work with a stove flue?