Depuis un peu plus de 1,5 ans, nous avons restauré la maison en 22 Grand rue et maintenant il est prêt!
Nous avons eu beaucoup de soutien et d’aide et nos voisins qui ont résisté à la poussière et le bruit que nous avons fait. Il y a encore du travail à faire dans la cave, mais les trois appartements spacieux laquelle nous avons créé sont prêt à emménager Maintenant, il est de temps de célébrer! Venez jeudi prochain, le 7 Août à 18h00 à jeter un oeil sur ce que nous avons fait (Facebook – Event).
Restoring a wall starts with removing the old plaster and all the odd pieces and covers which are not original, such as pieces of cement, gypsum, wood, plastic etc. The best way to remove the old mortar from the surface is doing it manually bit by bit with a pick hammer.
To remove harder (cement) mortar you need an electronic percussion hammer, but this is very heavy to use and you have to do the finish with your pick hammer afterwards anyway. If you want to leave the stones visible afterwards, you have to remove the old mortar to a depth of about 2 cm between the stones. Don’t worry about stones moving or falling out, but put a tarp under your working place to catch them, especially when working at height.
Afterwards, you have to wash the wall with water (either with an ordinary water hose or with a Karcher) to remove all the loose, dusty pieces. You wash from top to down and don’t pose the nozzle directly into the joints to avoid washing out the sand from the inner parts of the wall. In case you need to replace stones, take the same natural stones which are used in your wall. You place them in a lime mortar bed. Mix 3 parts of fine sand (0/3) with one part of lime hydraulique (NHL 3,5) and water. It’s difficult to say how much water you have to add as this depends on how much water is in the sand, but you should be able to form it by hand. If it’s too dry, it will fall apart, and if it is too muddy, it will drop out.
However, you can replace the stones immediately after washing the wall.
Plaster and paints
If you want to plaster walls made of natural stones you SHOULD use a lime mortar. It supports the exchange of humidity and lets the wall breathe. It is comparatively flexible and moves with the wall and does not crack. A cement mortar mix is very strong and does not support the breathing of the wall. Sooner or later, you will get the problems with dammed up humidity and cracks on the surface or the stones. Adding impermeable supplements to a lime mortar mix is also reducing the ability of the wall to breathe.
The best temperature for plastering is between 12°C – 20°C. It shouldn’t be too cold or too warm, thus you can’t really plaster in summer. The mix would be drying too fast and crack.
A traditional lime plaster
The traditional lime plaster (l’enduit traditionnel à la chaux) consists of three layers:
Le gobetis (rough coating)
Le corps d’enduit (main layer)
La couche de finition (finish)
Even though the composition of the three layers is different, the application is always done by hand. We are using hydraulic lime for the first two layers and air hardening lime (chaux aerienne) for the finish. Lime gets its mechanical firmness through an exothermic reaction by adding water. Hydraulic lime contains also minerals and is therefore drying much faster, can be applied thicker but is not so shock resistant. Chaux aerienne is pure lime and you can add as much water as you like (e.g. for lime wash paint) to work with. It dries in air for several weeks or months and gets it shock resistance while drying. It can be applied only in very thin layers.
Le gobetis (rough coating)
This is a semi-liquid mix of 2 parts of sand (0/3 – 0/5), 1 part of hydraulic lime (NHL 3,5) and water. It is necessary to have a good grip for the following couches. The maximum thickness is 7 mm. Experts are throwing the mixture by using a normal sized trowel with their backhand on the wall. For the amateur this is very difficult. Make sure, that your wall is damp. However, afterwards you have a rough surface with a good grip for the following layer. If you want to only close the joints and leave the stones visible, then you can skip this stage.
Le corps d’enduit (main layer)
The second layer is the most important layer of your enduit. It gives your wall the final shape and protects it by its thickness. You apply it 48 hours after the gobetis, but make sure your wall is damp enough.
Mix 3 parts of sand (0/3) with 1 part of hydraulic lime (NHL 3,5) and water. This mixture should have a thick but creamy consistence and will be applied with a trowel. If it’s too wet, it will crack. You smoothen it either with your trowel or a taloche. The layer is 2-3 cm thick.
For closing the joints and letting the stones be visible afterwards, you apply the mortar mix with a small trowel and press it into the joints. Let it dry a bit and sleek the joints afterwards with your small trowel or with a medium damp sponge.
La couche de finition (finish)
You apply the final layer about seven days later. You mix 3 parts of sieved fine sand (0,8) with 1 part of air hardening lime and water. Color it with mineral pigments but respect the color palette of your environment. Damp your wall before you start. Apply a thin layer of max. 1 cm and smooth it with a taloche. That’s a tough work!
To get a very fine, smooth surface, you can also use lime and or gypsum in combination marble powder. Mix 1 part chaux aerienne, or fine gypsum and three parts marble powder in water until you get a soft creme. You might divide the parts of marble powder with fine, sieved sand Colour the mixture with pigments if you like. Soak the pigments in water before adding it to your enduit. Try it with small amounts of ingredients to get a feeling for the handling and to find your right colour. Lime, plaster and marble powder and your wall underground are changing the intensity of the pigments. I always prepare several samples on the same underground material.
Apply your enduit with a maximum thickness of 1-2 mm and smoothen it with a taloche. This procedure you can repeat several times with different colours but always in very thin layers. At the end you need to protect the surface. I like to use linseed oil to encourage the colour or Savon Noir:
first layer: 1 part savon, 3 parts water
second layer: 1 part savon, 2 parts water
third layer: 1 part savon, 1 part water
Apply it with a brush the first two times, apply the third layer with a taloche. Start from down of the wall to avoid drops (which dry immediately and are visible afterwards). Be careful with linseed oil, it really darkens the colour!
You can apply enduit on nearly every foundation as long as the it is dry, even, has no fissures and a unique surface. Some needs more preparation, e.g. plasterboards needs to be painted with an acrylic paint for bonding of the enduit.
Insulation of an old, stonewall house is done with the renewal of the external and internal plaster as described above. These walls are usually 40-70 cm thick, + 3-5 cm external plaster and + 1-3 cm internal plaster.
Mixing hemp into the corps d’enduit improves the heat transfer coefficient. In that case, your corp d’enduit will be about 7-8 cm thick.
When you are thinking of installing an energy-efficient heating system, then choose a wall heating and/or floor heating.
Any kind of applied external artificial thermal insulation will lower the ability of the wall the breath. As a result, the humidity will stay in the wall and either leave to the inner parts of the house if these walls are just plastered with lime mortar, or stay inside the wall in case the inner walls are also improperly covered.
To improve the heat transfer coefficient you need to lower the humidity in the walls, which you will make with the re-plastering as described above and with the accompanying restoring measures such as applying a gutter, restoring your old windows, doors, the roof and floors.
So much work!
However, what I described above are the ecological and, from the material point of view, rather inexpensive methods to plaster walls. You only need time and some experience. Contrary, there are a lot of ready to apply products (ecological and non-ecological) for a bigger amount of money (and with some chemicals inside) available in DIY stores.
It has been a long time since I wrote about our activities, we simply had a lot of work and no energy at the end of the day to write about what we did, just few minutes for some photographs we could spare.
Well, we did a lot:
all necessary beams had been replaced (24!), all new most of old one’s are sandpapered and treated
all floors had been made (rafters replaced, paved with our lime-hemp-plaster-sand mixture)
we built the structure for the upper apartment, a 76 sq.m place with an 24sq.m attic, including electricity and water supply
built in the upper new staircase
Finally, we started painting the ceilings and plastering the walls with lime & pigments in the upper apartment, the attic is nearly finished.
and we learned a lot:
about the successful lobbying of those involved in providing electricity and right materials by setting up rules which partly makes no sense (e.g. a socket for fixed telephones and TV in the main bedroom or a 2.5 m² single line for a 400 W air dome), not to speak of the disallowing of IP-driven sockets and LED light bulbs because you need to install the old system too.
that, when we want to shift the main electrical meter just 30 cm we have to pay the renewal of the electrical infrastructure outside as the cable is too old and not safe enough anymore (but we could use it further if we wouldn’t change anything!)
that we need a permission when we want to re-plaster our facade (which was not the case when we did it on our office three years ago). This was lot of paperwork but at least, we got a permission, with very detailed descriptions of the materials to be used which is good to know but I got the feeling that there might apply different rules for Fitounaises 😉
about the cultural differences in living habits, which results in skipping our idea to build a utility room as French people don’t like to use a washing machine commonly
We got a lot of help and advice from friends and neighbors, who helped us to find through the jungle of rules and restrictions and encouraged us to go on with our work. And, despite of the widespread practice in renting flats with as many rooms as possible, we kept our idea not splitting the space of each apartment in several small 9 sq.m rooms but having one bedroom, a bathroom, an open kitchen and a spacious living room. We are sure there are some people who like this concept.
There were a lot of things I did not take into account when I was writing that our floor in the first level will be ready last weekend. I was a way too ambitious!
As always in an old house, a lot happens on the way you can’t see in advance.
E.g., when removing the rest of the old floor, we found a fake wall and had a 2 sq.m area with about 20 cm of concrete. This alone took half a day to remove it. Before we could demolish all parts of the old floor, we also had to build a frame for the new staircase to the upper level which means putting in a new beam (dig the wholes and close it after placing the beam).
And then, the demolition of the two old staircases was not done in an afternoon. Another three old beams needed to be removed as they were cut when the staircases were built-in. Huge wholes were left, at least one we could use to place a new beam but for two other beams we had to make new wholes.
A neighbor passing by among all the dust, said it looks very pharaonic 😉
Finally, we needed one day to bring all the rubble to the dump site, 4.5 tons! Since today, we saw and lay the rafters so that we hopefully tomorrow start to put the floor fill on our 75 sq.m first floor.
It’s really a stressful time for us as we need to work a bit for real money in our company , organize our household (yes, it’s necessary to clean the house from time to time, wash clothes, buy some food stuff) and do this restoration work. There is not much time left to write in detail about our activities, therefore, just a short summary of what we did in last two weeks:
We went public and we
took out 75% of the floor in the first level (7 trailers of debris!)
placed four new beams there
cleaned four old beams
removed the old plaster from the facade at Grand rue
built a cage for the staircase from level two to level three and finished the floor at third level
started restoring the first old interior door (it’s going to be beautiful!).
Tomorrow we will finish the sub floor at first level and remove the rest of the old floor. At the end of next week we would like to have the floor on that level ready.
When we bought the house it was clear that we need to renew the roof. The roof was built in the traditional manner, with terracotta tiles. Over many years water penetrated some beams, the rafters and walls and it was in disastrous condition. What we didn’t know was how should we repair it. So we asked several people, looked at several houses, searched the web with the result of being more confused at the end. Of course, we wanted
to make it as sustainable as possible by using traditional materials
When looking at the roofs around us, we saw roofs covered in the traditional way with old or modern tiles and roofs covered with patterned Ethernit plates, looking like old tiles. We already did a roof with traditional tiles few years ago and know how much work it is. Therefore we were captivated by the idea using Ethernit plates. I checked the material descriptions and ask at local DIY superstores for prices. All in all, it would have cost about 11,000 € on material for our roof of 88 qm! A bit discouraged, we reflected about the possibility to use our old tiles as this would reduce the costs dramatically. So we did! First, we untiled the smaller part of the roof, cleaned those tiles which were not broken and replaced an old, rotten beam, repaired another one and placed two new beam between them as the distance was too large. Also, we built a Mezzanine in 2.50 meters height to be used as storage later but also to be able to reach the roof from inside as the room all together is a bit more than 4.5 m high.
On the smaller part of the roof we put new rafters on the beams and covered all with planks, a tar-bitumen foil and then replaced the tiles. The bottom tiles we fixed with screws, the upper one’s with lime mortar. It took us about two weeks, interruptions because of heavy rain and wind caused some interruptions. Taking the tiles down, cleaning them, bring them up again, mix the mortar and bring it to the roof, place the tiles: we were exhausted and the outlook of having to do the bigger part of the roof was not really funny. After another heavy rain we looked closer to that part of the roof and it hasn’t got that many leaks than the other part, the beams were still o.k. and the tiles seemed to be not that old and in a very good condition. In parts it looked more like a seedbed so we cleaned it with a Karcher first and then reinforced the rafters, mortar the loose tiles and replace the broken ones’. Also we had to replace the dormer window and to remove the old chimney. In particular, I cemented about 500 of the 1.144 tiles. I was nearly living on the roof 😉 and I enjoyed it somehow. It was warm and sunny most the time and the view from there is just spectacular.
A difficult part was the roof ridge as the two parts of the roof arrived in different heights now, so we had to be creative again: we placed a tailor cut plank in the middle and filled the interstices with lime mortar and protect it with lead. After, I cemented the ridge. The work was done just the day before it started raining again, and it is water proof!
It was a lot of work, we spent a lot of time but saved a lot of money.
I am cleaning old tiles, tomette, terracotta, cement tiles, glazed tiles, different seizes, tiles we found inbuilt in walls, on the floors we have to renew or simply on walls. All together, I already cleaned about 50 sqm. It’s not an intellectual challenge, its physical. I feel every muscle in my arms, from my hands to my shoulders, it’s even hard to write on a keyboard after hours of cleaning. My work place is an old wooden chest we found in the house, it’s perfect because it is even, I can perfectly lay down a tile with one side on the wooden frame and hammer away the 5-7 cm thick layers of plaster and/or gypsum with my chisel. Some people told me that I need to lay the tiles only in water for some hours and all the plaster and gypsum will be removed, but that’s not true. I tried it, put some tiles in a tub with water for a week. The water was a bit limy and the layer on the tiles got muddy which to remove was a big smearing. While removing the layers of plastic, paper and cartons from the floors, we found some journals from 1964! I guess this is the younger part of the house, some terracotta tiles must be much older as they are handmade and look very old. The only challenge I face is to stay motivated, to not throw all away, to bear the dust and smells of the last 70 years. Well, that’s a mental challenge 😉 However, I always remind myself how beautiful they will look when cleaned and laid on the new floors. There is another effect: I can think about my intellectual work, e.g. about the methods and content for the e-commerce workshop I have to give for the family business project end of March, or about this blog entry.
We thought we emptied all, but during the last weeks we took more plaster of the walls, removed some layers from a floor and thus, generated another 2,5 tonnes to bring to the dumping ground. Amongst some very old asbestos tubes, which to dispose was quite expensive. After all, we started to build a new floor in the third level. We want to be sustainable, re-use old materials if possible and if we need to buy new material, than it should be as natural as possible. So then, we thought of building the floor with hemp, as this is light, natural, antiseptic and a good insulation against temperature loss and noises. A bit of research was necessary to find a company selling it and we were wondering why it’s so difficult to get this kind of stuff. However, we bought it at http://www.materiaux-naturels.fr and here is the recipe:
10 parts hemp fibers,
3 parts sand,
2 parts air lime,
2 parts gypsum,
water and of course, a mixer.
You need to find a measure, we used our bakery bowl 😉 to have always the exact proportion. The hemp fibers needs to be the first in the mixer, with a bit water to let them swell a bit, than add the sand, water, lime, water, gypsum. Mix all until you get a pulp, not too liquid, not to strong, something like mashed potatoes. You have a bout 15 minutes to bring it onto the floor, than it’s set. The whole floor dries for several days, depending on temperature and humidity of your environment and it smells when the lime carbonation starts. To finish the floor, you need to cover this layer with air lime-sand screed, which can be done immediately after placing the first layer with the hemp fibers. Both together will be a perfect underground for tiling with old or handmade tiles, e.g. terracotta tiles.
So, the house is empty now. All the stuff which was inside we brought to the waste disposal sites, all the little walls are removed and now, we can see clearly damages on the beams, roof and the outer walls, can make plan how to continue.
We have to renew the roof, this we knew from the beginning. Also, this we discovered while emptying the house, some of the beams under the roof are damaged by water infiltration exactly there, were they lie in the outer walls. To exchange them is not only a lot of work but also very difficult to realize as they are about 7 meters long, heavy and need to bring up 12 meters! As they are not damaged by termites, it might be possible to keep them. After searching the web we found two solutions:
blaze repair plates
replacement of the rotten parts with resin
An architect confirmed that any repair might be better than replacing a beam. It might be impossible to find old beams from the same wood, in particular in this length. When using new wood, we might risk future problems as the wood is probably dried chemically and will move during the next years until finally settled. Let’s see what the specialists recommend us when visiting the house.
Despite of this, we need a scaffolding. We’ll probably buy one as renting costs about 100 € per day. It seems to be possible to get one in our size for about 2000 €. Finally, we have to redo 4 facades and buying might be the economic solution.
Information were to find a scaffold are very welcome!