Sterling Timber and Damp - Fungal Rotting

Particularly in older buildings, fungal rotting can be a huge problem. There are many variations, but all stem from the same source; moisture and nutrition being available so that the fungi can thrive. Some of the most common problems treated by Sterling Timber and Damp are:

• Brown (true) dry rot
• White dry rot
• Wet rot
• Decaying timber
• Spalting
• Zone lines

The Problem

Dry rot (Serpula lacrymans) 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.

The main causes of dry rot in British buildings are attributed primarily to the serpula lacrymans fungus and somewhat less so to the antroda vaillantii (fibroporia). Both species of fungus cause brown rot decay, preferentially removing cellulose and hemicellulose from the timber leaving a brittle matrix of modified lignin. Eventually the decay can cause instability and collapse in houses and other wooden structures.

Early catastrophes caused by dry rot weren't limited to houses either. British ships of the line were victim to this fungal agent of disaster too. Thomas Wade's posthumously published 'A Treatise on Dry Rot in Timber' cited examples of ships that were so riddled with dry rot, their upkeep quickly overtook the cost of construction.

Photographs on this page are courtesy of Safeguard Europe Ltd., whose products we use in treatment of fungal growth.

Sterling Timber and Damp - Identification

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 sterilisation) often have to be taken when treating dry rot outbreaks over and above those necessary when dealing with outbreaks of other wood-rotting fungi.

If you have any suspicion that your building may be affected by dry rot, wet rot or another fungal contamination, please call us on 0800 136 874 for a free, no obligation survey and estimate.

Typical indications of dry rot include:

• Wood shrinks, darkens and cracks in a 'cuboidal' manner (see picture)
• A silky grey to mushroom coloured 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 'cottonwool' 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 coloured spore dust frequentky seen around fruiting bodies.
• Active decay produces a musty, damp odour.

Sterling Timber and Damp - Treatment

Paradoxically, dry rot will only affect timber that is damp, typically affecting timber with a moisture content in excess of 28-30%. 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 sterilisation.

There is no one size fits all solution

Different problems and different fungus varieties all require different treatments. For an accurate assessment of what is needed in your own property, you can rely on our experienced team to identify the cause and offer the most appropriate, efficient and cost-effective treatment.