Q Three years ago I bought a totally refurbished ground floor flat. New rendering and hung tiles, new roof, re-plastered throughout. The damp course is apparent and bitumen has been painted below the damp course wall and ground. I am now selling the property, and have been told I have rising damp due to hygroscopic salt contamination, inhibited by unsuitable soft plaster mix. The surface plaster measures bone dry on the Protimeter. There is no surface evidence of damp; all walls are painted plaster clean and clear of any mould, condensation or any obvious signs of damp. Skirtings are natural pine and also read dry. Why am I getting conflicting readings, must the walls be treated, how many more years may it take before deterioration may show through? What are the alternatives to evacuating and all the plaster being removed? Do I have any recourse with the original builder for latent claims?
A From what you describe it sounds very much like someone is 'inventing' unnecessary work and perhaps leading you up the path! This highlights the need for an independent opinion such as we provide. Hygroscopic salts do not cause rising damp - they are a consequence of rising damp. You state that plaster surfaces and skirtings are dry when tested with a Protimeter yet you have been told you have hygroscopic salt contamination!? It just does not add up. If you did have hygroscopic salt contamination this would very probably cause a reading on a Protimeter (if they were there in sufficient quantity) due to their moisture attracting properties. How was it decided and who decided that you had hygroscopic salt contamination? Were plaster samples removed from site and tested in a lab? If your walls are dry there is no need to seek recourse - in any event caveat emptor (buyer beware) would be relevant. Perhaps we should speak - please give me a call.