Chris Plastow
Ok, damp proof failure, very rare. If the windows are leaking, there will be a damp stain on the exterior too. Guttering faults will cause moss or algae ( green) growth on the exterior for more than a year before it gets inside. Ventilation, will show as black spot mould. Driveway too high, this will cause damp at skirting level. No damp will cause interior plaster cracks, this is a different issue . Let me know if you need more info
