All Wet Rot fungi require higher moisture contents than Dry Rot (Serpula lacrymans), at least 30% (fibre saturation point), and many will achieve optimum growth and decay rates between 45 and 60% moisture content.
Wet Rot (Coniophora puteana), the cellar fungus, is the commonest cause of wet rot timber in buildings.
Characteristically it causes a brown rot of Softwoods. Decayed wood splits along the grain, and across grain cracking is not as deep as that of Dry Rot (Serpula) and much smaller cubes of woods are formed by this cracking.
The decay is commonly confined to the wood interior, leaving a thin surface veneer of apparently sound timber. The Fungus produces very little surface mycelium, but thin, brown, branching strands are regularly formed on the surface of attacked timber. The fruiting body is rarely found on timber buildings.
The small cuboid cracking of the decayed wood is helpful in confirming identification, but should not be relied on alone for diagnosis.
Damage by Wet Rot (Coniophora puteana)
The correct identification of Fungal growth found during any inspection is an important part of any Remedial work.
Some growths may be relatively harmless whilst others may indicate the need for particular Remedial measures.
There are a number of Fungi which cause decay in building timbers. These are classified as either of the ‘Wet Rot’ type or as ‘Dry Rot’
Wet Rot (Coniophora) may attack in buildings where there has been a serious leak as a result of faulty gutters and downpipes, or failed plumbing. It can also cause decay in exterior painted joinery and other timbers. See our information about dampness.