Lime Plaster.

Did you know cement, gypsum plaster and acrylic paints cause damp in older houses? And that lime mortar and plaster, clay and linseed based paints solve a damp problem, and there’s no such thing as ‘rising damp’? My beliefs were re-written last night after a short read. Apparently the first lot create a barrier to moisture, which my poor understanding figured was a good thing, and the second lot are permeable. This permeability allows moisture to breath in and out of walls naturally whereas an impermeable barrier causes moisture to build up behind it. Being stuck there with no means of escape it causes damp. The expert who wrote the article was quite exercised by a whole industry created to ‘solve’ damp problems by these widely held misunderstandings. Excessive water ingress as with my current problem will cause damp but these are usually obvious structural faults often easily fixed. My father in law had three builders fail to overcome damp when it was obvious it was caused by a broken down pipe, a half hour job to fix, and their remedies, using concrete, gypsum plaster and an injection DPC might actually add to the problem. As I struggle to relate this to Donald Trump all I can come up with is that democracy must be allowed to breath and his administration shows all the signs of creating an impermeable layer and the US is getting damper by the week.