Wood Decay Fungi
The fruiting bodies of wood decay fungi vary in size, shape and colour. The type of fungi encountered by building inspectors & pest controllers usually reside in poorly ventilated sub-floors, below wet areas of the home, exterior timbers and in areas that retain water in the soil. The durability and type of timbers are factors along with the temperature and environment. Destruction of affected timbers varies with the symptoms involved.
Removal of the moisture source usually alleviates the problem. Fungal decay is attractive to termites and if the problem is not rectified it may well lead to future termite attack.
Wood decay by fungi establishes growth in unsealed, split, exposed timbers and/or timber sections. Timber joints and/or sections that have gaps due to shrinkage or poor joinery and have not had ends properly sealed could have established fungal decay that is not visible, this decay may advance to extensive fungal decay within a short period of time. To minimise further decay it is recommended to seal all gaps with sealant and/or paint as a matter of priority.
Decay fungi can cause severe structural damage to any wood member, even wood species such as redwood and cedar. All that is needed is a source of water in contact with the wood. Decay will occur in untreated wood in direct contact with ground, cement or concrete, or exposed to a source of moisture such as rain seepage, plumbing leaks or condensation. Wood kept dry will never decay!
Brown rot fungi feed on the wood’s cellulose, a component of the wood’s cell wall, leaving a brown residue of lignin, the substance which holds the cells together. Infested wood may be greatly weakened, even before decay can be seen. Advanced infestations of brown rot are evidenced by wood more brown in colour than normal, tending to crack across the grain. When dried, wood previously infested will turn to powder when crushed. Often, old infestations of brown rot which have dried out are labelled as “dry rot.” This is really a deceiving term since wood will not decay when dry.
When white rot attacks wood, it breaks down both the lignin and cellulose causing the wood to lose its colour and appear whiter than normal. Wood affected by white rot normally does not crack across the grain and will only shrink and collapse when severely degraded. Infested wood will gradually lose its strength and become spongy to the touch.
If you suspect you may have a fungal infection in your home call RIP Integrated Pest Management Services. We can assess the problem and guide you towards a solution to the problem.