Tuffeau Walls Revealed

Our house is mainly built of tuffeau, a limestone extracted in the Loire Valley. As part of the renovation of the house we have decided to expose as much of the tuffeau stone walls within the interior as possible. With a building this old it is not surprising it has been transformed many times during its lifetime, with the result being there are layers and layers of different wall coverings on some of the walls.

The wall coverings include modern crepi (a sort of interior render), ceramic tiles, lime wash and mortar. We have decided to strip back all the walls to the bare tuffeau in order to give ourselves the opportunity to inspect the walls and repair where necessary. The plan, in as much as there is one, is to leave the tuffeau exposed on the interior walls while heavily insulating all exterior walls. In this way we can retain some of the original character of the building while not racking up enormous fuel bills and wasting tonnes of energy.

Tuffeau wall covered in plaster and concrete

Cleaning the tuffeau is a very messy but not too onerous a job, although you do need to approach it with some care. For example, in the upstairs apartment the tuffeau was covered in a thick layer of plaster over concrete, which we were able to chip and prise away with a palette knife and hammer without causing severe damage to the tuffeau.

Tuffeau wall in apartment uncovered

Because tuffeau is so soft it needs to be able to move, so the mortar between the blocks must also be soft to ensure that the stones are not held rigid and so crack.  To make sure that we didn't damage the mortar we had to be extra careful when removing the concrete from over it.

Uncovering the tuffeau in the hallway

With the renovation downstairs we have the added complexity of rising damp which is causing the tuffeau to disintegrate.  This has been made worse by the walls being enclosed, with the result that they could not release their moisture.  Maybe even worse, the crumbling tuffeau has filled in the gap between the plaster blocks and the tuffeau wall enabling the damp to bridge across. 

Cleaned tuffeau wallin the hallway

Once the plaster cladding was removed we very gently tapped the mortar on the tuffeau to loosen it and then used a palette knife to lift it from the surface of the tuffeau. We are having to be particularly careful towards the base of the wall due to it being very damp and crumbly.  Not an ideal way to make the foundations for a 10m high house!

Once we remove all the old plaster/mortar covering we will clean the joints and remortar them. We hope the result will be a rustic yet beautiful tuffeau wall that will last for many years to come.