The UK is known for its cool, wet climate. Last year provided a good example of this, with one of the wettest summers on record and flash flooding across much of the country in August and September. Such weather can lead to penetrating damp in properties, often due to blocked gutters, drain pipes, drains or water rapidly running off hard surfaces.
The high levels of moisture ingress caused by this can cause particular damage to timber in properties – leading to issues such as wood rot. Forecasters are now predicting an above-average chance of winter being wetter than normal over the next three months. With this in mind, it’s important to know what causes wood rot, how to spot the warning signs of a problem, and what to do if you identify a potential issue.
What causes wood rot?
Wood rot is caused when timber becomes excessively damp (above 20%) when moisture enters a property. Particularly aggressive storms may also cause roof tiles to be displaced or damaged, and if roofing membranes become defective, there is also a much higher chance of water ingress.
Excess moisture can also be caused by poor ventilation within a property, and as property occupants close windows to try to keep warm during colder weather, damp issues such as condensation typically become more common.
Identifying wood rot
The most common visual sign of wood rot is timber that changes colour or looks like it is splitting, crumbling or disintegrating. There are two different forms of wood rot (white and brown rots), including what we call wet rot and dry rot, depending on the types of fungi and conditions at play.
Dry rot decay is caused by fungal growth as airborne spores germinate when they come into contact with a food source such as timber, which has become damp. This form of rot can be highly damaging in a property, as it can severely impact its structural integrity and can spread aggressively from one area of timber to the next. Contrary to its name, dry rot needs moisture to flourish and grow, and can be hard to spot because it often grows in areas with reduced ventilation where people do not look, such as under floorboards or behind plaster away from light.
Wet rot is not normally as harmful as dry rot, and will only occur where the moisture source is located. It attacks timber in much wetter conditions, making it a common cause of structural defects and decay to timber window frames. When excess moisture is absorbed by timber it can allow fungal spores to germinate and produce mycelium which produces enzymes to break down the timber, leading to it losing its strength.
Wood rot treatment
When it comes to treating wood rot, the first port of call should be to locate and stop the cause of moisture ingress. When tackling a case of dry rot, exposure work will be required to trace the full extent of the outbreak, as it may have spread many metres from the moisture source. To treat the fungus growing on walls and timbers, affected wall plaster may need to be removed.
For wet rot, the decayed timber needs to be replaced or cut back to ‘sound’ timber – the wood that remains structurally intact and in a safe condition and finally, the remaining timbers should be treated with a fungicidal spray to protect them whilst they dry. The most vulnerable sections of timber are usually those that bear into the wall structure because it is at those points where the timbers typically tend to absorb moisture from the masonry.
Replacement can include splicing in new sections using steel plates, bolts and timber connectors fixed through the timber or timber resin splice.
Ultimately, timber plays a very important structural role in many of our homes and buildings and steps need to be taken to check on its condition. At Peter Cox our specialist surveyors have experience in identifying and treating wood rot in properties all across the UK for decades. If you are concerned that you might have identified some of the signs in your home, then visit our website or book a wood rot survey today at https://www.petercox.com/our-services/dry-rot/