The true Dry Rot fungus is the more serious of the two, requiring fast specialist action to avoid extensive damage. It is malignant and will spread even through thick walls in search of fresh timber to attack. Affected timber is brown, dry and brittle with cuboidal fractures and can be crumbled by hand.
It requires over 20% moisture content for spore germination. Fine greyish hyphae strands
develop from the spore spreading to form mycelial growth which varies from grey to pure white in wet conditions. Sporophores or fruiting bodies give off millions of spores in the form of red dust. Dry Rot surveying may require exposure work - behind paneling and plaster or under floorboards before the complete extent of the outbreak can be confirmed.
The nature and biology of fungal decay makes it necessary first to remove the underlying source of moisture behind the outbreak, e.g. a failed damp proof course, broken downpipes or leaking service pipes either exposed or buried within walls or floors.
Roofing failure and leaking gutters are particularly damaging allowing water to spread over large areas before being discovered.
As with woodworm, water ingress is the main culprit and a building's weakest point is generally the roof. As this represents part of the common areas, the importance of keeping the roof in good order becomes a major issue for the landlord or residents association. There is no substitute for a programme of regular maintenance to prevent water penetration.
For flat owners in multi-occupation blocks the problem is the difficulty of isolating and containing these out-breaks. Dry rot in particular is a major threat as outbreaks in one flat can easily re-occur elsewhere. |
