ASK THE EXPERT

Douglas Kent, technical and research director at the Society for the Protection of Ancient Buildings (SPAB), answers your queries Q Several of the brick faces on the south-facing wall of our Grade Ii-listed cottage are crumbling. Should I replace them or cover the wall with render?

Unless your wall suffers from extreme weather exposure or there is evidence of a past render, I would not cover it. My advice is to identify, and try to address, the cause of deterioration. This may be leaking gutters, the use of cement rather than lime for repointing, or it may just be the inherent nature of the bricks. Defective bricks are hard to overcome, although some can be removed and then reversed to hide decay. Coloured mortar can be used to build up eroded brick faces, but skill is needed to obtain a good, long-term colour match. Thin brick slips are sometimes used but don’t tend to perform well. For severe damage, bricks will need to be cut out and replaced with ones that closely match the existing, and laid using a suitable (usually limedbased) mortar. It is best to allow the bricks to tone down naturally than to artificially age them. Second-hand bricks are best avoided.

Q We are thinking of buying a ‘locally listed’ house. Could you explain what this means?

Local listing aims to protect buildings that are of historic and architectural interest but do not meet the criteria for being listed nationally. Despite offering less protection than national listing, it will still strengthen the case for retention of a building, and the effect of a planning application on a locally listed building will be considered by planners when making decisions.