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Your guide to dry and wet rot: What is the difference between wet rot and dry rot? How do you identify and treat dry rot and wet rot?

Extreme example of dry rot

Are you a property owner? If so, you know how essential it is to take good care of your property in order to keep it in pristine condition. Sometimes, however, disaster strikes. Whether a flood, a plumbing issue or an unfortunate incident with a washing machine, when water penetrates your property it’s not just surface areas that can suffer damage. 

One of the most serious issues that can arise from dampness and moisture is the presence of wet rot and dry rot. Both are types of fungi which can penetrate wood and timber within your property and they thrive in damp and wet environments. They can spread through masonry and cause severe damage to timber, weakening the structure of your property and causing potential health issues for the occupants.  

Knowing what wet rot and dry rot are and how to identify and treat them is essential for protecting your property and understanding how to deal with any issues that may arise. In this article, we discuss the difference between dry rot and wet rot in your property and how to identify the telltale signs of its presence.

What is Wet Rot and what is Dry Rot?

Wet rot and dry rot are two common forms of wood rot that can affect both residential and commercial properties. However, they differ in terms of the types of fungi that cause the decay, the conditions under which they grow, and the symptoms they produce. 

Wet rot is caused by a fungus that thrives in wet, damp conditions and can spread through wood, masonry, and even plaster. It is the most common type of rot and tends to prefer areas that remain damp over long periods of time. There are many variations of Wet Rot, but the most common type is Coniophora Puteana.

Dry rot, on the other hand, is caused by a fungus called Serpula Lacrymans. This fungus prefers drier conditions and can spread through wood and masonry throughout your property much quicker and easier than Wet Rot. Dry Rot, despite the name, still requires damp conditions and moisture in order to spread, but at a much lower humidity level. It’s possible that Dry Rot fungus is already present on the timber in your property, as wood is a great absorber of water and continued high humidity can create the perfect environment for a rot outbreak. 

What are the main differences between Wet Rot and Dry Rot?

It’s easy to confuse wet rot and dry rot as they share many similarities, both can cause serious damage to your home, and they can both spread quickly. However, there are some important differences between the two that will help you determine what form of rot you may have. 

Wet rot fungus is caused by fungi that thrive in moist environments. It’s most common in areas that don’t get much ventilation and have moisture buildup due to issues such as penetrating dampness or rising dampness. Common areas where wet rot can be found are behind walls, in bathrooms, and in basements

Wet rot requires continued moisture in order to sustain itself, the fungal growth of wet rot will cause wood to become soft and spongy. It will spread itself by emitting spores which find their way to other areas of moisture, latching on and feeding from the wood. Wet rot can be less destructive due to its need for continued water, but since the wood has been weakened, it makes it easier for pests and other organisms to cause further damage. 

Dry rot is caused by fungi that can thrive in drier environments, it obtains its moisture from wood and doesn’t necessarily require large areas of dampness to spread. It can be found in spaces with low humidity, such as attics, crawlspaces, and window frames, but still requires humidity of around 20% to sustain itself. Unlike wet rot, dry rot can cause wood to become brittle and easily breakable which can be a serious problem with the structural integrity of your property. 

Dry Rot will spread itself quickly throughout your property, infecting large areas and leaving a trail of fruiting bodies. Due to its ability to spread in low humidity and attack different types of wood, dry rot is considered the most serious type of rot. 

How do you identify Wet Rot?

The most common signs of wet rot are discolouration, softness, and cracking of the affected area. The affected wood will start to become darker in colour, and may even change to a yellowish-brown. The infected wood can become soft and spongy to the touch, as well as exhibit signs of cracking and even crumbling in your hands.

Another sign of wet rot is the presence of fungal growth or fruiting bodies. Fungal growth can often be seen on the surface of the wood, or within the cracks in the wood. Fruiting bodies are the reproductive structures of the fungi and may appear as tiny mushrooms on the surface of the wood. In addition to the physical signs of wet rot, you may also notice a musty or mouldy odour coming from the affected area.

How do you identify Dry Rot?

The most common signs of dry rot are the presence of cuboidal cracking, where the wood splits into small, roughly cube-shaped sections. This is due to the fungus absorbing the moisture content from the wood. The affected timber may also appear darker in colour, with a distinct reddish-brown hue. 

In advanced stages of dry rot, you may begin to see visible fungal growth on the surface of the wood, which can take the form of fluffy white or grey patches. A distinct smell can also point towards Dry Rot, with an earthy or musty-like smell in affected areas.

Our guide to wet rot treatment – how do you treat Wet Rot

Treating wet rot can be a daunting and overwhelming process, but with the right knowledge and experience, it can be made manageable. When dealing with wet rot, it is important to understand the different stages of treatment and how to correctly identify and address the issue.

The first step in treating wet rot is to identify the source of moisture and the extent of the damage. If you don’t know the cause, a professional service can help pinpoint the problem and make sure that it is properly addressed. Once the source of the moisture is determined, the affected area should be thoroughly dried out and treated with a fungicidal solution to prevent any further damage.

The next step in treating wet rot is to repair the damage that has been done. This may involve replacing damaged wood or applying a preservative solution to protect the wood and prevent future damage. It is important to remember that wet rot can spread quickly, so it is essential to take care of the problem as soon as possible.

Finally, it is important to take steps to ensure that the wet rot will not return. This can include improving ventilation and air circulation or installing a dehumidifier to keep the area dry and ensure good damp proofing. A professional service can help make the process of treating wet rot easier and more manageable by providing advice on the best way to identify the source of the problem and help to ensure that the problem does not recur.

Our guide to dry rot treatment – how do you treat Dry Rot

Professional treatment of dry rot involves a multi-stage approach to ensure that not only the rot itself is removed, but any causes are repaired to prevent dry rot in your property in the future. Treating dry rot can be a complex and time-consuming process which is why it is important to act early to eliminate a dry rot attack.

The first stage of the process is to assess the affected area to identify the extent of the damage and the best course of action. The affected area must be thoroughly cleaned and any damaged wood removed. In some cases, it may be necessary to replace the affected wood with new, treated wood. Appropriate treatments such as fungicides and sealants may be applied to help prevent future outbreaks. 

Now you know the difference between wet and dry rot, its time to manage it

It’s clear that wet rot and dry rot pose some serious problems for your property and can be difficult to identify and treat. Once you have identified or suspected the presence of rot it’s important to act quickly to find a solution to prevent further damage to your property. 

With the help of The Preservation Company, you can manage your wet rot and dry rot concerns using a professional and trustworthy service. We are a leading expert on wet rot and dry rot, offering a range of services from inspection and diagnosis to repair and restoration. Get in touch with us today to learn more about how we can help protect your property.

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Gavin White
About the author

Gavin White

Gavin is an experienced and trusted building preservation and restoration professional with over 40 years of expertise in the field. He is the founder of the Preservation Company, which he established in 2009, and holds certifications in CSTDB, CSSW, and SWD. His dedication to preserving and restoring historical buildings has earned him a reputation as a highly skilled and respected professional in his industry.

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