If you have eliminated the possibility of a leak, (pardon the pun) or condensation dripping from the cold cistern, household bleach is your answer. Not the cheap stuff that smells just like urine (just adding to problem).
One other thought, make sure the flooring under the slate tiles is not harbouring damp, as damp has a tendency of smelling like pee.
If laid on suspended timber flooring, make sure all air bricks are clear, if on concrete floor eliminate rising damp. Floor covering will have stopped natural evaporation.
One other thought, make sure the flooring under the slate tiles is not harbouring damp, as damp has a tendency of smelling like pee.
If laid on suspended timber flooring, make sure all air bricks are clear, if on concrete floor eliminate rising damp. Floor covering will have stopped natural evaporation.
