We’ve got an unexplained patch of damp at the top of our main stairs.
It’s on the wall to the right of the stairs (opposite side to banister) about 30cm x 30cm and lines up with the third step down at a height of 10cm above the first floor level (see pic).
It is a terraced house and we assumed it was from next door – it is not a mirror image of ours because the houses are staggered and next door has been converted into flats so their stairs are not next to ours. However a builder working in the top floor flat claims it is not originating from there (although we only have their word) but we have not had access.
Alternatively, from what we can work out without measuring, the ground floor flat has an extractor fan on that wall although it is about a foot lower than the damp patch – do you think this could be possibly cause it? I can’t imagine where the damp from there goes and it seems too much of a coincidence but surely the damp would be at the same level – ie below, not above ground floor ceiling level. We have had access to this flat and I noticed very minor damp on their ceiling that would possibly correspond with our damp and also indicate it came from above.
Any other ideas as we are baffled?
What sort of tradesman would we get out to advise us – would it be a surveyor?
Thanks in advance.