Hi,

I am looking to insulate our house. External insualtion is out - we're in a conservation area. The walls that I am particularly interested in are solid stone and solid brick.

So I am looking at internal insulation preferably without losing too much internal space. I've been thinking of some sort of insulation batts with a studwork/laths and lime plaster.

I can see that something like kinspan thermawall or kooltherm would do the job from an insulation point of view but I'm not sure about them as 'green' materials.

I've seen various woodchip board but that seems to need very thick sections to give decent insulation, same goes for the sheepswool stuff.

Gervase has suggested the hemp/lime mix and I've seen the 'magic'aerogel recommended.

I'd welcome and suggestions, experiences.

thanks

Hi Tom

At the moment those solid walls dont seem to offer much in the way of benefit, esp the north facing ones. :) And heating them is a serious business.

looks like the hemp stuff may be the way forward then.

thanks

thanks Tom

cornices? Nothing so grand.
some internal walls upstairs are laths, and some ceilings have escaped the plasterboard and aertex. the rest is plaster on walls, a thin scrape of lime plaster except where previous owner has had injected dpc and concrete on bottom 3 feet.

Well, I've just ordered some kingspan to experiment with in the coldest room.

I can understand thermal mass having a benefit with external insulation, but without external insulation I cant get the walls warm. I am going to try some kingspan on the inside of the external wall. The joists in this room dont go into the external wall so Im going to put the insulation right down the wall below the internal floor and put insulation between the joists under the floorboards. I'll irritate my wife by leaving it like that for a while before putting clay or straw board over it and a skim of lime plaster.

I'll strip the run of concrete from the bottom of the wall and put battens up between the insulation and the wall. Although I'm unsure from what I've read if I should do that - or just have the insulation right up against the wall?

sorry tony,

Is that 'No. Gap is best'
or 'No gap is best'

I've learnt to be cautious of punctuation on internet forums!

cheers tony

Hi Tom,

Thanks for the offer but its the front of the house, which is the biggest (strange shape) and oldest (1750-1800) which is the issue.

Is the room very high-ceilinged? Is there good ventilation? Might the room benefit from reducing the height? Rooms were only built high to keep the coal fumes from killing everybody, I understand. We have a similar room, a bedroom, it is damp and cold and very high. We thought of sheepwool and were advised by the supplier to hang dampproof textile on the wall before putting up battens, then the wool, then presumably plasterboard on top. This would make the room much smaller, especially if applied to two walls as proposed and it's not large as it is. Also, don't want to have to remove skirting boards and window cills, as I fear we would have to. Reduc ing the height is not within our diy skills. External insulation might look odd against the rest of the terrace of houses, tho it's not in a conservation area. Am following this thread with interest!

The "Practical refurbishment of solid-walled houses CE184 (PDF)" has some good examples, however mostly using an air gap:

http://www.energysavingtrust.org.uk/uploads/documents/housingbuildings/ce97.pdf

chrisc, there are quite a lot of details I dont agree with in the first reference. Unventilated voids behind the wall insulation then no ventilation gap above the roof insulation.

I would not therefore call them good! Also mixing insulants and picture of poorly laid and too thin loft insulation was horrid.

Posted By: chriscPavawall advertises as a "breathing wall solution" -- has anyone used this and does it work as claimed?

http://www.natural-building.co.uk/pavawall.htm" >http://www.natural-building.co.uk/pavawall.htm

These guys seem to be taking note of decrement, not just U-value so worth checking out. I still think min 75 of sprayed hemcrete wd do it better.

Pretty good - but all due to be made obsolete by multifoil once the manufs can stop fighting legal and technical obstuction and get down to marketing the products and application systems and make-it-easy accessories that they already have developed.

Hi,

I have an old victorian house and would like to insulate the walls internally.
It's 4 storeys, mid-terrace.
The walls are about 50cm thick, and although this thread talks about the benefits of thick walls I don't really experience that in this house.
It costs alot to heat, and that's only to a bearable heat, nothing near to hot.

The rooms are mostly quite small, so eco-materials are out, as they'd take away too much room space.
I was thinking of using Kingspan Kooltherm K17 rigid phenolic insulated boards attached to the walls with adhesive.
These boards are laminated to plasterboard, so I wouldn't need plasterboard aswell.

1) The Kingspan website says these are insulating, dry-lining and vapour-control all in one.
Does this mean that these boards will let the walls breathe?
I'm worried about all the comments in this thread about the need to let your walls breathe : will this product allow breathing to happen?

2) I'm going to internally insulate as and when rooms need redecoration.
This will be happening from the top down.
If I don't get round to doing the lower floors for several years, will this cause problems ?

3) When I do get to doing the ground floor livingroom, this a high ceiling and a beautiful original cornice.
I don't want to have to remove and replace the cornice.
If I just insulated upto the cornice, will this cause problems?
Will it also negate the effect of the insulation as all the heat will escape at this cold spot ?

4) The roof has been leaking, and water has been running down to the external wall and soaking into the wall.
The damp can be seen in the top two floors, the top floor is built into the roof so there's only a small amount of external wall in this room,
and the water has got most of the way down the wall in the room below this.
The roof is being replaced (and insulated) so the cause of the damp will be cured.
Gutters and downpipes will also be checked, and the walls re-pointed to make sure there are no other ways for damp to enter the house.
Once all this has been done : how long do I have to wait before I can insulated the walls internally?
I want to wait until the walls are damp-free, so that I'm not sealing in any damp.
Do I need to measure will some kind of moisture meter to make sure the walls are dry enough to insulated?
What damp-measurement do they need to be below before it's safe to insualte?

Many Thanks for any advice

Thanks for the advice Nick.
I don't have a problem with condensation or mould anywhere in the house at the moment.
Would that mean it's less likely to happen once I insulated?

Re-creating the moulding sounds expensive.
I'll have time to ponder on that conundrum before I get round to insulating the livingroom.

My advice -- french drain yes, external insulation. leave floor alone, lime plaster walls. avoid membranes

When was house last lived in?