Dampness may be caused by various other defects and the effect of dampness can harm the building in many ways. So called specialist damp proofing work usually includes chemically injected damp treatment and waterproof plasters; however these can be expensive and will harm historic buildings. In a listed building this would constitute an alteration requiring listed building consent; however due to the resultant harm such consent would not be granted. Modern damp treatments merely conceal the problem without identifying and removing the root cause of the dampness; they create cold walls which increase heat loss and can soften lime mortar which increases the risk of structural failure. We follow Historic England advice on a conservation approach to dampness; identifying the root cause of the problem and recommending appropriate and effective repairs. In the above case dampness had been a problem for 60 years and thousands of pounds were spent on damp treatment but without success. The new owner followed our recommendations and the building dried out quickly.