Wet / Dry Rot
Thankfully wet rot decay is typically confined to areas where the timber has become and remains wet. However, it is not a case of just fixing the initial wet rot. You have to fix the source of the water ingress to ensure that the wet rot does not re-appear. After the source of the water has been identified, the treatment of wet rot can continue which generally involves the replacement of timber within the infected area.
A professional property survey will be able to identify and reveal the full scope of any wet rot problem and the sources of any water ingress. Using specialist surveying tools, wet rot can be surveyed even in unexposed areas within a property. If a property survey reveals the presence of wet rot then the appropriate wet rot treatment will be recommended.
Dry rot is a wood-destroying fungus that is found in most parts of the world. Although it affects forest timbers, dry rot is best known for its ability to destroy timbers in ships and buildings. Dry rot can remain active in timber down to 20% moisture and can attack dry timber. The fungus can grow throughout the fabric of a building if conditions are suitable. It can penetrate through brickwork and masonry, and behind plaster, decaying any timber in its path.
Decaying timber which develops 'cuboidal' cracking is usually overgrown by masses of grey-white mycelium.
Identification of Dry Rot
It is important to identify whether timber decay has been caused by dry rot or another wood-destroying fungus such as one of the wet rots. This is because dry rot has the ability to travel through building materials other than timber, giving outbreaks the potential to spread quickly through a building. For this reason, additional measures (e.g. masonry sterilization) often have to be taken when treating dry rot outbreaks over and above those necessary when dealing with outbreaks of other wood-rotting fungi.
Typical indications of dry rot include:
Wood shrinks darkens and cracks in a 'cuboidal' manner (see picture)
A silky grey to mushroom colored skin frequently tinged with patches of lilac and yellow often develops under less humid conditions. This 'skin' can be peeled like a mushroom.
White, fluffy 'cotton-wool' mycelium develops under humid conditions. 'Teardrops' may develop on the growth.
Strands develop in the mycelium; these are brittle and when dry and crack when bent.
Fruiting bodies are a soft, fleshy pancake or bracket with an orange-ochre surface. The surface has wide pores.
Rust red-colored spore dust frequently is seen around fruiting bodies.
Active decay produces a musty, damp odor.
Dry Rot Control and Treatment Dry rot will only affect timber that is damp, typically affecting timber with moisture content in excess of 20%. For this reason, removing the source of moisture should form the core of any dry rot eradication strategy.
Timber can become damp for a number of reasons. Among the most common causes are leaking washing machines, shower trays, baths, condensation, etc... The dampness can also come from outside the building, for example, leaking roofs, rising dampness, or dampness penetrating through walls. Whatever, the source of the dampness, if it is rectified and the timber allowed to properly dry out, the dry rot will eventually be controlled. However, it is not always possible or practical to be sure that the timbers will remain dry in the long term.
Therefore, it is important that secondary measures are taken to defend against re-infection. Any affected timbers should be removed and replaced with pre-treated timber. Any remaining timbers at risk of being affected by the dry rot should be treated with an effective fungicide.
Where the dry rot has passed through the masonry, it should be isolated using physical containment and/or masonry sterilization.
Contact HLS Northwest Limited who are approved and experienced contractors. We can provide a free quotation (for homeowners or for pre-purchase services see the 'Types of Survey' tab above). We also provide fast and friendly service.
Whether local to the Lancaster, Morecambe, Carnforth, Kendal, Keswick, Windermere, and all Lake District area or across the Northwest, we are here to help you.