See guidelines from RICS / Historic England / PCA. UK surveyors must now identify and recommend treating causes not just symptoms, as was the case. Remember causes are; groundwater, rainwater, mains water and vapour. Symptoms include: rising damp, damp stains, salts, rot, mould and condensation.
It is important to understand that dealing with damp is normally a staged process. You should deal with the obvious defects first (including for example matters such as ventilation, ground levels, and lifestyle). Then allow a period for monitoring, and natural evaporation and re-assess before moving onto other treatments.Stage 5 guidelines from RICS / Historic England / PCA
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