Walls built with cob can last for centuries if properly maintained.
The most important aspect to repairing a cob wall is to identify the reasons why the repair is needed. The underlying reason needs to be rectified before the cob repair is carried out.
We have found the most common causes for the necessity of cob wall repairs in Cornwall are below along with some examples:
Water penetration
- Inadequate weather protection at the top of a wall will allow water to penetrate wall causing erosion and de-stabilisation.
- Over time, the build-up of ground levels can prevent plinths from drying out and cause the wall to become saturated.
- Vegetation against the wall may prevent drying out.
Failed cladding
- Cement renders and modern impervious paints are two of the main causes of a wall collapse.
Failed roof timbers
- Defective timbers on the roof structure can cause the walls to lean outwards or develop major cracks.
Subsidence
- Subsidence, erosion or softening of the supporting soil can cause damage or cracking to a cob wall.
Bees
- Bees bore into the cob, which slowly weakens the mass of the wall.
Rodent damage
- Rat tunnels and nesting chambers within a cob wall can cause it to fail.
There are various ways to repair a cob wall, depending on the nature of the problem, and these can be found here:
We believe in a sympathetic approach to the repair of cob buildings in Cornwall as they form an important part of our heritage.
Cob Wall Repair in Cornwall – Listed Cob Wall Repair in Cornwall – Cob Wall Repair Truro