Interior insulation of an old house

[the-rabouin]

Hello, and first of all, best wishes to everyone for this new year

I have an old house from which I would like to isolate the ground floor. The walls are thick (60 cm), made of stone, covered with plaster inside (plaster + plaster or paint) and outside (plaster). The floor consists of a non-insulated concrete slab, overlooking a cellar. Almost all carpentry was changed five years ago.

Due to the almost total absence of insulation on the ground floor (except that symbolic of the windows), there is a feeling of cold (especially on the floor) and the humidity causes some damage to the walls (mold and paint blistering in some places). However, the inertia of the walls is interesting (restitution of heat in winter and coolness in summer).

As I plan to settle elsewhere in the medium term and my means are not unlimited, this immediately rules out the solution "from the outside" for obvious reasons of cost hey hey and this supposes "homemade", with the help of relatives, using not too expensive materials, as I did for the floor. In short, like many people, I am looking for "not too badly too cheap" .

A friend who is "in the game" offers me interior insulation of the walls (only the walls facing the outside) with plasterboard lined with insulation, taking care to leave an air gap between the insulation and the Wall. He also told me about "barbacanes" (sort of pipes inserted into the base of the walls) in order to evacuate the humidity from the walls.

Now here are the fears and pitfalls related to this project:
1. Doesn't this solution still risk trapping moisture and causing the insulation to rot? I had thought of lime, earth, straw, flax, etc., but the cost price of the goods is not necessarily that economical, it's a big job, it takes chandeliers to dry and all this for a discussed result it seems in terms of thermal insulation.
2. To allow the walls to breathe, should the interior and / or exterior plasters be blown off?
3. Some walls will cause problems due to radiators and heating pipes.
4. There is not much room to insulate window frames
5. What efficiency on arrival? almost no insulation had been carried out by the former owner who considered that it was useless because of the inertia effect of the rock mass on which the house is built. According to him, insulating would have the effect of trapping the cold in winter and canceling out the advantage of freshness in summer. Besides, a neighbor who had his house insulated from the outside (also on the same rocky mass) did not notice any significant improvement ...
6. Do you also have to insulate the slab (problem again because of water pipes and electrical conduits attached to the slab)

Obviously, I remain convinced that insulating is always the right choice, but what I have read here and there on the insulation of old walls seemed to me to be quite contradictory. So I don't want to do anything stupid, that's why I defer to your wise advice;)

cordially

[loopyng84]

hello, I tested this product the type is nice and will guide well! http://www.brique-isolation-chanvre.com/ , for my part I did my cooking with it and I am satisfied with it !!!!!

[of]

For interior insulation, the best is excellent insulating, natural, light, rot-proof cork - Ecobio Materials, for example - but wood fiber is also excellent and less expensive. See the different types of insulation http://www.climamaison.com/dossier-isolation-thermique-maison.htm#.UbmWtZxGO-0. Isover offers the Optima and Actis system of high performance thin insulators.

[djo59]

1. As long as you don't dismantle it's pretty, the one who will dismantle . (we agree that you talk about ba13 with either glass wool or polymachintruc) Regarding the insulating plasters (lime, straw, ..) unless you put thick ones .... but they cut the feeling of cold hence the comfort felt and the degrees less, while letting the walls breathe.
2. If the exterior coating is waterproof, yes it is better to blow it up otherwise waterproof coating + iti, where does the water come out? Inside I don't know.

3. In iti, all the interior fittings need to be redone (radiator, electrical outlet, etc.)

5. In interior insulation you lose all the inertia of the load-bearing walls. See the internal partitions if they can bring you inertia. Next for inertia is worth seeing the use of the house and the inertia you want. House for weekends, little inertia, we get to heat it is hot. In permanent housing, a large inertia acts as a buffer.

6. It would not be bad but in reno . You raise the existing slab with the following (raise the doors, sufficient ceiling height, ...), or you break the existing slab and make a new one

Personally I had to buy a stone house a month ago in the same genre. My program was ITE in 14cm in wood wool or rock + plaster on nergalto (cost comes back from materials about 40 € / m²; mp if you want my suppliers) and insulation of peripheral walls buried to insulate my slab while neutralizing the thermal bridge of this one. So:
- No need to touch inside (it saves time and money)
- I insulate (even if not at the top) my slab (ceiling too low to raise and lazy to break the slab)
- My walls breathe again (like you plaster exterior and interior plaster + paint

Otherwise the lime plaster solution seems to me to be the least expensive, widely used and compatible. It lets the walls breathe while cutting the feeling of cold.

[rpsantina]

Hello everybody

Due to the almost total absence of insulation on the ground floor (except that symbolic of the windows), there is a feeling of cold (especially on the floor) and the humidity causes some damage to the walls (mold and paint blistering in some places). However, the inertia of the walls is interesting (restitution of heat in winter and coolness in summer).

I also own a very old farm (some walls are over 100 years old) ...

In my opinion, your problem comes from humidity.
Your concrete slab on the ground conducts moisture in your walls which must also have a concrete exterior coating. Suddenly, you trap part of the water in your cellar and the rest goes up in your walls.
As it evaporates, the water lowers the indoor temperature like in a refrigerator.
So, for your heating, opt for a radiant solution (Like a small rocket stove, or low temperature solar thermal see the website of the association APPER to glean ideas)
If you don't touch the exterior plasters, I don't see how you will improve your comfort.

Before renovating / insulating old walls, we must understand the mechanisms used by our ancestors. Lime is the best / only solution to preserve their internal structure. Knowledge lost after the war because time and materials were scarce given the scale of the work.

[Trept1934]

With interior insulation, the charm of old stones will disappear, but energy saving requires!
Old walls often store moisture, so it is good to keep an air space (2 to 3 cm which is the best insulator) between the wall and the insulating complex. Another argument, old walls are rarely straight ...
So laying on metal rails or wooden battens of an insulating + plastering complex .:

A very good natural insulator: treated sheep wool, which does not fear humidity, unlike rock wool.
Good renovation.

[puntrialmoor]

and by mixing, we sometimes find this solution:
northern walls often not very visible: exterior lining + autoclave wood cladding, and south walls insulated from the inside, uninsulated partition walls which leaves a lot of visible stone inside as well as for the north walls.

after all, why want stone everywhere, there are really beautiful contemporary / old mixes (rehabilitating barns, farmhouses ...)

another complementary solution: the greenhouse in front of one of the stone walls on the south side, like that no insulation (or very little) around this wall, and the feeling inside / outside of this room extended by the greenhouse makes it very very good, it is good for morale in winter (so less depression, less meds: good on calculating the well at the wheel!)

I think that in your case as much not to think single solution, it will be much more creative