Insulation-Studding old house

Ginger83

Hi all, I'm going to be studding an old country house soon, using 3x2 and 4x2.
What insulation would be best for the job?
I'm planning on using 200mm rockwool between joists on 1st floor and in attic but had the feeling it might sag over time if I used it on the wall partitions.

Any advice appreciated, thanks

brendankelly

Google breaking the mould by Joseph Little first. Old walls needs to breath and if they cannot breath you will have mould etc. Rockwool will sag even between the joists. Sheep's wool is better but more expensive. Hemp mats are also better. There are a few breathable options available and I will pm them to you if you wish.

AckwelFoley

A common mistake made by people is they think if they pack fiberglass into a stud beyondwhat you should thinking you will increase the thermal value - you wont

If you try and pack 200mm into a 100mm stud - by pressing it together from 200 to 100 you lose alot of the termal value of the insulation, and although much of the time its main purpose is for its accoustic properties on internal walls you can also ahve an issue with bulging slabs from the pressure behind the slab - in time they can bulge apparently (ive never seen it, but was old about it)

mfceiling

As snyper says don't force 200mm insulation into a 100mm partition.
If you are putting insulation into the partitions you can buy special adhesive "hangers" which stick to the plasterboard and have a very sharp needle point which goes though the insulation and you bend it up to stop the insulation from sagging. Try Capco or Tennants in dublin to buy them.
Also as brendan points out - old houses mightn't take to overkill on insulation without adequate ventilation - might be worth looking into this further to save any hassle down the road.

brendankelly

I would be totally against advising people to dry line stone houses. The walls needs to breath and problems will arise later. There are breathable materials that can be used to give a healthier home.

Ginger83

Hi, thanks for the replies.

what options are available? I was planning to insulate and dryline but am having second thoughts.

I planned to move studs 1 inch away from walls to stop damp travel

salamander27

brendankelly wrote: »

I would be totally against advising people to dry line stone houses. The walls needs to breath and problems will arise later. There are breathable materials that can be used to give a healthier home.

What sort of problems could arise? And could you let the wall breathe to the exterior rather than the interior?

brendankelly

salamander27 wrote: »

What sort of problems could arise? And could you let the wall breathe to the exterior rather than the interior?

The problems that not could but will arise are outlined in the reports by Joseph Little in breaking the mould are basically that you create the perfect living conditions for mushrooms and moulds behind dry lining. I have seen 6 inches of clay that was decayed vegetation behind dry lining.
In my opinion You could let the wall breath to the exterior but you would need some sort of heat recovery system. Ordinary vents would let in cold air and defeat the original plan..

richieoflynn

I own an old house, approx. 100 years old with thick stone walls. A friend of mine who was in the drylining business a few years back did 3 rooms for me. What he did was fix galvanised (I think) metal brackets to the walls, attached lenghts of metal track to the brackets and screwed insulated plasterboard slabs to the track. You're left with a good sized cavity between the 2 walls and very good insulation. I think the insulation on the slabs is very efficient, more so than the older type slabs that used aeroboard. You also don't have the messing around with the rockwool / glasswool stuff and won't have to worry about sag, touching both walls etc. never mind the horrible conditions of actually handling it :-) Obvisouly you loose a bit of square footage in the room but I haven't noticed the reduction in size considering the house is already very small.

As for ventilation, in 2 of the rooms there's open chimneys that were left open so there is definately some sort of air circulation but as to what level I don't know. There's also bricks built into the lower section of the wall that allows air flow in under the raised floors which is in the same 'air space' as the open chimney. I'm delighted with the results and it's a nice cosy house now with no signs of mould but of course I can't comment on the conditions of the inside of the old walls :-)

Paul.C

If it was my own house or if the clients budget allowed, id use Kingspan or quinntherm