Above is the living room on the day I first saw it. Below is what it looks like now, denuded of its crumbling wooden floor and the joists that were laid under it. It was all in very poor condition and unsalvageable due mainly to moisture, which then made it attractive to certain wood-boring insects who had done damage as well. Part of the problem was those vinyl plastic tiles that had been laid over the old wood floors, probably in the 1960s or 1970s, and would have trapped moisture underneath. All the bad wood has been taken away and burned now, and the remaining wood upstairs has been treated to repel future hungry insects. An important issue now is how to rebuild the base of the ground floor.
There is not much depth below the hearth to the dirt floor. The floor is overlaid with broken slate and cement that originally had the joists crossing it, with the ends of the joists stuck into hollows of the granite walls. The trick now is to update the underfloor with materials that will allow for better insulation than the old ways, but at the same time allow gradual evaporation through the floor of water vapors from underneath, which can then dry out in the heated air of the main living quarters rather than deteriorate the floors and walls with damp.
So much of this is contrary to what we expect in modern buildings. In more modern construction (anytime post 1920 in the main), one wants to waterproof the underfloor completely with plastic and cement, and keep the interior completely insulated and heated. Old houses like this one however, with thick stone walls, need to be able to "breathe," letting water vapor escape through porous materials like lime in the bottom floor and walls. Otherwise, moisture will creep around the waterproofing and cement below and go up into the stone walls, where it will encourage fungus and other deterioration.
After several discussions with our builders about these issues and many hours spent studying UK and French websites about conservation and restoration methods for old stone houses, I finally found a website that seems to explain all of this fairly well (in French). "Maisons Paysannes de France" is a website dedicated to helping owners and builders understand how many of the older houses were built, and how they can be sympathetically updated to improve their functionality without jeopardizing the stone or columbage they were built with. http://www.maisons-paysannes.org/maisons-paysannes-de-france/bienvenue/ and http://www.maisons-paysannes.org/restaurer-et-construire/fiches-conseils/ (the latter providing specific advice about insulating an old structure for better heat retention without damaging it).
I highly recommend it to any of you who are thinking of renovating a place built before the early 20th century, or who just are interested in architecture and engineering. Those of you who are more clever with Google Translate than I am may even find a way to get most of it into English. I've tried, but the builders' terms don't translate very well. For example, the layer of stone that goes down first on the compacted earth is known as the "hérisson," a term of art. The literal meaning of hérisson is "hedgehog" though, so if you go by Google Translate, it will be telling you to lay down a layer of hedgehogs before you do anything else.
So much of this is contrary to what we expect in modern buildings. In more modern construction (anytime post 1920 in the main), one wants to waterproof the underfloor completely with plastic and cement, and keep the interior completely insulated and heated. Old houses like this one however, with thick stone walls, need to be able to "breathe," letting water vapor escape through porous materials like lime in the bottom floor and walls. Otherwise, moisture will creep around the waterproofing and cement below and go up into the stone walls, where it will encourage fungus and other deterioration.
After several discussions with our builders about these issues and many hours spent studying UK and French websites about conservation and restoration methods for old stone houses, I finally found a website that seems to explain all of this fairly well (in French). "Maisons Paysannes de France" is a website dedicated to helping owners and builders understand how many of the older houses were built, and how they can be sympathetically updated to improve their functionality without jeopardizing the stone or columbage they were built with. http://www.maisons-paysannes.org/maisons-paysannes-de-france/bienvenue/ and http://www.maisons-paysannes.org/restaurer-et-construire/fiches-conseils/ (the latter providing specific advice about insulating an old structure for better heat retention without damaging it).
I highly recommend it to any of you who are thinking of renovating a place built before the early 20th century, or who just are interested in architecture and engineering. Those of you who are more clever with Google Translate than I am may even find a way to get most of it into English. I've tried, but the builders' terms don't translate very well. For example, the layer of stone that goes down first on the compacted earth is known as the "hérisson," a term of art. The literal meaning of hérisson is "hedgehog" though, so if you go by Google Translate, it will be telling you to lay down a layer of hedgehogs before you do anything else.
So far, we are talking about trying to build an underfloor like the one above (diagram from Maisons Paysannes). We are still looking into the best materials for each layer, all of which I would like to make as "green" as possible without sacrificing stability. Jim will advise us further in coming days, and I'll post some translations soon too, so we will all know our hedgehogs from our lambourdes!
RSS Feed