solid walls....

kevineaton77

hi everyone, hope you are well.

ive just bought an old house circa 1910 and bits of it have solid walls.

ive just insulated my office (floor and walls and ceiling) with 40mm cellotex in between battens for floor and walls and 20cm top up loft insulation for the roof and it is now by far the warmest room in the house. it is in fact toasty! it was freezing and i had to work in a hat and several fleeces. the floor was concrete with a carpet covering.

the 47mm battens are attached to the wall at 24 inch centres with 40 mm cellotex filling the gaps, and then i have expanding foamed the tiny gaps between the cellotex and the battens, then put 18mm ply on the face (its a workshop, so it doesnt need plasterboard).

the walls are 1960's in the office part of the house and i think they have a small cavity.

i did it as a bit of an experiment and given the success, i now want to do some more rooms. i have several rooms that have solid walls on 2 faces.

so i have a few questions....ive been doing a lot of reading and understand that i may get damp problems if i insulate inside a solid wall. the walls of the rooms are not freezing and they arent damp, but they are cold. ive got loads of cellotex left over so im itching to sort it out. i know i can do the required work myself, as opposed to external insulation which seems to cost a lot more for the materials and also would be a pain to do because some of the rooms are on the first floor and it seems to require a lot more expertise to do..i might not be able to do it myself.

my questions are....

can i just bang up some wood battens and insulate in between as i have done in my office. its easy, cheap and i can do it.

do i need to do warm battening, use vapour barriers etc, use the very expensive plasterboard/insualtion/vapour barrier stuff that kingspan/cellotex sell?

part of one of the rooms has a chimney breast in it - do i need to insulate this bit?
thanks for your advice.

FreeBear

kevineaton77 wrote: »

do i need to do warm battening, use vapour barriers etc, use the very expensive plasterboard/insualtion/vapour barrier stuff that kingspan/cellotex sell?

Insulating some solid walls is on my list of things to do here - I'm favouring the warm batten method as it reduces cold bridging by the battens and lower quantity/cost of timber. The Celotex already incorporates a vapour barrier, and the foam itself is inherently water resistant. Battens, foam, and plasterboard will work out cheaper than the bonded foam/plasterboard as well as being easier to handle. If you use 1800x900mm sheets of plasterboard, you should be able to do the entire job single handed.

I'll leave others to comment on the chimney breasts. As for damp in the walls, as long as the exterior isn't rendered with cement or had a modern waterproof coating applied, IWI shouldn't cause any problems. If you are worried about possible damp, you could always leave a 25mm air gap between the brickwork & insulation.

kevineaton77

thanks for the advice. had you considered external insulation?

FreeBear

kevineaton77 wrote: »

had you considered external insulation?

No. A few properties in my area have had EWI done, and it looks butt ugly especially around the windows. Add to that, the high cost and it effectively seals any moisture in to the walls - Not a major issue with cavity construction, but not good for solid walls.

That said, one could use woodwool boards and render in lime, but that would bump the cost up even further.

For my property, I'll use warm battens & Celotex boards on the upper half which is solid brick, and do one room at a time - This will keep the costs down and gives me the opportunity to redecorate along the way. For the bathroom, I think I will go for woodwool boards & lime plaster in order to manage the inherent damp in that room. Also gives me an excuse to do yet more polished plaster which I quite enjoy doing.

new_owner

I have insulated all the downstairs walls and under the floor with solid insulation.

I ended up fitting insulation directly to the wall and then pinning plasterboard through the insulation and to the walls with plastic pins and some fire rated pins.

It has made a huge difference to the house.

I decided against the baton method in favour of direct pinning. Makes putting up shelves a little more interesting but easy enough.

I have no issues with damp however I did read breaking the mould before under taking this project and kind of followed the guidelines and reasoning there. Once I did all the calculations I found it quite straightforward.

Planning to do all the upstairs rooms exactly the same way as soon as I can face all the decorating ...