17 Sep 2011

Building stone walls

Building stone walls is an age-old practice. Until the use of concrete took over, stone cutting and building was so important to all forms of construction in France that the trade which had the largest number of workers was that of stone-masonry. Building stone walls happens to be one of my activities during the summer holidays. I do other building work of course, but this endeavour, largely considered by members of my family as futile, since these are outside walls which serve no obviously useful purpose apart from creating prospects of their being able, in a year or two, to sit on the terraces thereby created and watch the sun go down, is perhaps my favourite of all, along with woodwork. This article includes some pictures that attempt to show a current job in progress. The best of them (the one below and the black and white shot) were taken by a friend of mine, Christophe Goussard, who is a professional photographer (www.goussard.net).

One of the main difficulties in stone-wall building can be finding the raw material. Stones vary enourmously on their colour, texture and density, but they are always bulky and heavy. Transport is therefore usually the major cost involved and so you need to find them as close as possible to where you are building, and then find a way of carrying them. I use trailors behind cars, tractors or trucks, when I can borrow the latter two. It is best to have one that tips it's load, otherwise you almost double the work involved. In an ideal situation you would have machines to load and unload, but I don't. It is also important to unload the pile as close as possible to where you are going to be building, without that pile getting in the way. In other words, a bit of planning will make the job easier.

So far I have not had to buy any stone. There was some on the site to start with, and I have transported three other loads of about 5 tons each so far in order to build the two levels of the current project, which is not yet completed. So thanks also to generous donors who had some surplus. You need a hell of a lot of the stuff, and it should have variable sizes. Big ones that you need to have help to move (I also use a makeshift tripod and chain-hoist, as well as crowbars and planks) since they can weigh up to 200 kilos and maybe more, medium sized ones of between 20 and 50 kilos, and lots of smaller stuff to block and fill the nooks and crannies and create some variation. They should all have at least one face that is fairly flat, and a base that will lie reasonably well on the layer below. You can of course cut and chip them into shape with an electric stone cutter, or hammer and stone chisel. I use both (see top picture for handwork in process) and you need to do quite a bit of this to get good seating for each stone, especially if you are not using any mortar.

On this project, where the walls are essentially in-filled at the back with rubble and earth, I have dry-built everything, with the exception of the angles and the capping layer. In other words little or no mortar is used. In this case I have taken care to have large and long stones at the base when starting, and also to put in a longer stone every so often to help anchor things. The in-fill also contains a lot of small, stone, broken tiles etcetera immediately behind the wall, as well as the odd drainage pipe, to ensure that water-logged earth will not build up too much pressure in the future.

The house and its out-buildings are built into a slope, so the walls will create terraces that will later be partly paved and partly planted. This is why in the above shot you cannot see the uppper wall, set back from the lower level and less high. A staircase is under construction (see below), leading up through the walls to the house, alongside the barn that serves as a wood-shelter for the moment. I build it as the walls move along and up, thereby creating filling material to go behind the walls and create the terraces. The bottom wall, which is about 6 ft high, has a concrete foundation, whereas the smaller and lighter upper terrace wall (that is the one I am working on in the first picture), and which is about half as high, is built directly onto the compacted earth.

As you can see from the picture to the right, finding some good corner stones enabled me to build the entrance to the stairway. The wall section to the right of the stairway is finshed, whereas the part to the left will be continued on for a further 10 yards or so.

Below the walls and at the bottom of the slope is an artificial lake. Good for reflecting sunsets and to give birds and deer a drink. I hope to finish this project next summer. Wish I could work on it full-time, but I guess the break will give my hands time to heal!