Dry rot case study

One of our surveyors attended the property, at an appointed time, finding it to be a large detached house on a prime site. The property, being in a desirable residential area, offered enormous potential although in obvious need of a degree of refurbishing works.

Initial testing for internal dampness was made with the aid of an electrical moisture meter. The readings obtained indicated extensive problems throughout the building. An external inspection revealed localised rainwater penetration of the brickwork caused by defective guttering and downpipes, this was particularly severe to the front elevation. Our surveyor therefore focused his initial attention on the ground floor timber joists and floorings at the front of the building. With permission, fitted carpets were carefully lifted and turned back in this area. Fresh white fungal mycelium growth, sprouting between the timber floorboards, was immediately visible.

Sufficient sections of floorboards were lifted to enable our surveyor access to the sub-floor void. This revealed an extensive and very active outbreak of Dry Rot, Serpula lacrymans. The majority of the sub-floor void was covered in sheets of mycelium bearing rust coloured fruit bodies which covered several square metres, (see photograph). The timber floor joists and boards were decayed to the point of imminent failure and resultant collapse of the floor. Sections of wall plaster were removed from within the front alcove revealing a spread of mycelium behind the plaster exceeding 1.5 metres in height. The combination of rising damp, penetrating damp and inadequate sub-floor ventilation had provided perfect conditions for the germination and rapid development of the fungus. Further inspection confirmed our surveyors suspicion that the mycelium had penetrated the sub-floor brickwork and an additional active outbreak was found to have severely decayed flooring timbers in the adjacent room.

Our full report, covering the whole of the property, included for extensive remedial and improvement works to eradicate the dry rot, cure the dampness and substantially improve the ventilation to the sub-floor voids. This was presented to our customer for urgent attention and they were made aware of the possible danger of the floor collapsing.Until our surveyor lifted fitted carpets there were no visible signs of the active outbreak of dry rot or the possible dangers it was causing.