Torchis?

Le torchis
Where do I begin? Well perhaps the one thing I remember being baffled by when I bought my first ruin in France was what was the rough infilling between the beams and wall timbers. The temptation was to rip it out and replace it with something more approximating the plaster finishes I had been used to in England. Luckily I had an endless supply of locals to advise me.
They introduced me to the wonders of 'torchis'.
Torchis is what we call Cob in English and is a mix of clay, sand and vegetable fibre. You find it used all over the place in old French buildings, filling of half-timbered walls on colombage houses , for the interior walls and the insulation of the ceilings. 
 Torchis is a great material and has many advantages for building. 

Beside being natural and ecological, it lets the house breath and controls moisture levels to create a healthy atmosphere. Finishes that seals the surface form condensation on the face, supporting the growth of moulds which are just ideal for respiratory disorders.
When I start to renovate a building where torchis has been use in its construction I am always amazed how well it has stood up to the years of use. It isn’t untill you try and remove some of what is essentially mud pie and straw mix ,finished with a daube of lime paint, that you find how strong it is.
 Sometimes bugs have eaten away the supporting wood laths and you have to replace it, but usually you find it has done a good job of conservation the main timbers, being souple it moves with the carrying structure without fissuring, unlike in filling using brick or cement. 

As you probably can guess I love the stuff and could bore you silly with it’s virtues, like It is an excellent sound and thermal insulation, 10cm of torchis insulates as much as 23cm of solid brick or 50cm of stone. 
 On a technical note I will add it has a good thermal inertia, that is it is slow to take up heat and slow to cool down, so it it keeps the house cool in summer and warm in winter. 

Later I will try and explain the 'art' of applying torchis.