I’ve heard this quite a few times since I came to France. Although my own home has no torchis or at least none that you can see, many of my non-French neighbours have come across this term when planning their own renovations as French neighbours will often comment that the “torchis needs doing” in French of course!
Richard, my nearest English neighbour has become an expert in torchis this year as he has been doing up the whole of the front of his house in this traditional style over the course of the summer so here is our guide, with his tips, to torchis.
Torchis is a traditional method of render and depending on who you talk to is a mixture of either mud and natural fibres or a mix of water, clay and natural fibres (straw, hay, horse hair – Richard used hay and it was perfect!).
It’s pretty much the same as the traditional wattle and daub mixture that was traditionally used in the UK in days gone by. It’s used as a primitive, by which I mean ancient, form of plastering and you’ll come across it in many old French houses filling in the gaps in the wooden stud walls and with great impact as an external type of render in the colombage style houses seen in many parts of France.
Richard’s house needed external rendering and as it is a small but rather lovely house and very traditional looking throughout he decided to keep the traditions going by re-torchis-ing (I know it’s not a word but you know what I mean), the front walls, the old torchis being extremely worn out and patchy.
His neighbours tell us that the torchis method is preferred because it makes a great insulator by trapping air in the fibres; also as it is a natural material, the walls can “breathe” which improves insulation and finally it’s a fire retardant material – I’m not sure I completely agree with this but they say that clay or lime (which is often painted over the torchis) does not burn and the trapped air in the fibres can prevent the flow of fire.
Richard mixed it up in an old wheelbarrow and left it for long periods over the course of several weeks while he enjoyed the good life in France, returning to the barrow to mix in some more water to make it malleable when it was a bit dry and then pushing it into the holes and bare patches in his walls.
Top Tips for Torchis
If the space to fill is too big and the mix falls out – hammer some nails into the wood studs or place small branches in the gaps so that the mix has something to adhere to.
If you’re using mud in the mix, make sure you remove any stones, leaves or twigs and make sure the mix is wet enough.
Use a cement mixer to make up the mixture and save your time and energy to get the mix nice and smooth on the walls.
For optimum torchis performance and lifespan add the mix in three layers as follows:
Layer 1 – mix a bucket of sand, a bucket of lime, clay and a few handfuls of straw. Mix the elements dry in the mixer and add water gradually to make good sticky dough.
Put on the walls in a strong way and don’t smooth it – leave it rough so the second layer can hold onto the first level. As the mix dries out it will mostly like crack –it’s perfectly normal, just leave it to dry fully.
Layer 2 – the mixture should be the same components but with les straw. Cover over the first layer, take care to make sure any cracks are well hidden and then carefully smooth the layer over – you can do this by hand or any tool you think will do the job as well.
Layer 3 is essentially a topcoat. It should be little clay, a lot of water and lots of lime (lime milk). Make a nice smooth mix and paint it over with a big brush.