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Not long after moving into our house, we noticed the lower part of the walls in our downstairs toilet are damp to the touch and showing signs of mould. This is an external corner of the house (North facing). We had a damp specialist come out who said we had high moisture readings within the fabric of the plaster, suggesting rising or penetrating damp. He felt the property age (1930s) suggested it wasn't necessarily rising damp and the DPC was old but looked OK, so he said it was probably blocked/bridged cavities. An engineer opened the cavities and indeed found debris, which was apparently causing moisture to rise internally, so they've cleaned it out. However, it's been about a week and we're still seeing just as much dampness - almost with water pooling - where the wall and floors meet. When I queried this, the specialist said that will now be condensation, or that we have to wait about 4 months for it to dry out from the cavity issue. Is this right? And what can we do in the meantime?

Hi jenfthomp
Suggest you buy a de-humidifier (look for one with energy saving smart controls) and run this continuously in the loo. This will help the drying out process and will help identify the source of the damp. If you have solid floors there may not be a DPM so this may be aggravating your problem..
Regards S

Thanks, we just bought a dehumidifier actually so will try that. Is the DPM something different to the DPC? Do you need both? Thank you!

Hi jemfthomp
The DPC is a layer of impervious in the lower courses of brickwork, it could be strip plastic, rubber, etc or more likely in your case slate. The DPM (damp proof layer) is a layer of impervious material, like a sheet, it could be plastic, or bituminous paint, or tar etc, usually embedded within the floor layers.
The two do need to join around the perimeter of you room.
Regards S