Defects - Timber Flashcards
Name three common forms of timber defect.
- Dry Rot
- Wet Rot
- Insect Attack
What are the life-cycle stages of fungal attacks in timber?
- Spores - Spores in the air react with timber in the right conditions.
- Hyphae - Spores grow, producing fine white stands called Hyphae.
- Fruiting Bodies - The Hyphae germinate producing Mycelium
- Mycelium - Mycelium develop and spread feeding the attack further.
Describe the characteristics of Wet Rot.
Wet rot can either be a white or brown rot, and typically requires moisture content to be in excess of 40%. Occuring internally or externally, it can also occur in well ventilated spaces.
Describe the characteristics of Dry Rot.
Dry rot refers to the condition of the timber following the attack. Typically found in timbers with a moisture content between 15 and 20%, and prefers damp, unventilated spaces.
Dry rot is also more invasive and can spread through plasters and masonry, and even through party walls.
How can you tell the difference between timbers affected by wet and dry rot?
The location of the affected timber will typically guide diagnosis, however, wet rots will leave a damp, soft, spongy timber, whereas dry rots will leave a dry timber with cuboidal cracking and often crumbly.
What is the remedy for rot to timber?
First step is to eliminate any source of moisture and to dry out any affected timber, whilst removing the rotten wood and replacing with treated timber.
A fungicide may also be applied.
How do you identify insect attack?
The most obvious sign is the presence of numerous small holes caused by the larvae boring through the wood. In some instances, adult beetles can be seen emerging from the holes, most commonly in summer.
What is the remedy for insect attack?
The affected timbers will need to be cleaned down, and treated. Any unsustainable or unsafe timbers should be removed and replaced with treated timber. An insecticidal fluid may also be applied.
