My tanked basement used to get quite damp on the floor and it always puzzled me until 2018 when I discovered that the neighbour’s damaged foul drain had been leaking into the adjacent ground for an unknown period of time.

In my frustration to find the cause of the damp, I removed some of the tanking where there was minute cracking and signs of moisture, only to end up with a sudden and relentless ingress of liquid through the 130 year old soft brick wall.

The basement flooded to several centimetres and the smell was horrific !

Anyway, prior to the flood I would get the occasional fungi growing on the floor…