Wet vs Dry Rot - What's the Difference And Why It Matters

Rot is caused by certain types of fungi that feed on the wood's cellulose and lignin components. It’s a natural process that occurs over time, especially when wood is exposed to moisture or high humidity levels. Rot can occur in any part of a building that’s made of wood, including the structural framing, floors, and trim. It can also spread to other materials that are in contact with the infected wood, such as drywall, insulation, and even brick or concrete.

Although rot spores aren’t dangerous in themselves, the conditions they need in order to thrive can be. Buildings with excess moisture are a lot more likely to have damp and mould, which can be a serious risk to infants, older people, and those with respiratory conditions.

There are two main types of wood rot: wet rot and dry rot. Each type has its own cause and characteristics, but both can cause a lot of damage to your home.

Croft Preservation are Dorset and Hampshire's first choice for expert rot treatment. Read on for our complete guide to wet and dry rot, including their unique qualities, what sets them apart, and how each type should be treated.

What is wet rot?

Wet rot happens when wood is exposed to high levels of moisture for a long period. It usually occurs in damp-exposed areas like window sills, skirting boards, and roofs. It can cause wood to become discoloured, soft, and spongy, and can also result in fungal growth on the surface of the wood.

What is dry rot?

Dry rot is arguably the most severe type of rot. Unlike other types of wood rot, dry rot can occur in mostly dry conditions, as long as the wood has enough moisture to support fungal growth.

Dry rot typically begins in areas that are poorly ventilated, such as inside walls, under floors, or in crawl spaces. It can spread quickly, travelling through masonry and other building materials to the rest of the home. It has a pale, powdery appearance and tends to make wood feel soft and crumbly.

How do you tell wet and dry rot apart?

Because of their similar appearances, it can be hard to tell wet and dry rot apart. However, there are a few key differences that can help with differentiating the two:

• Wet rot requires a higher moisture content in the wood, usually around 50%, while dry rot can occur in dry conditions with a moisture content as low as 20%.
• Dry rot tends to appear as a powdery substance, with the wood often crumbling easily. Wet rot, on the other hand, often appears as a darker, softer area of wood with a stringy or fibrous texture.
• Wet rot tends to be more localised and only affects the area of the wood that’s in contact with moisture, while dry rot can spread across large areas.
• Dry rot produces distinct fruiting bodies, which are small, mushroom-like structures that can be seen on the surface of the wood. Wet rot does not produce these structures.

Although the above factors may give you an idea of the kind of rot your home has, your best bet is to have a professional look at it. They’ll have the tools and expertise to accurately identify the type of decay your timbers are suffering from, which will let them determine the right treatment to deal with it.

Are wet and dry rot treated differently?

It's important to use different treatment methods for wet and dry rot, since they have different underlying causes. This approach can help effectively address both types of rot and prevent them from causing further damage.

How wet rot is treated

Wet rot is caused by continuous exposure of wood to moisture, so the first step in treating wet rot is to identify and eliminate the source of the moisture. This may involve repairing leaks, improving ventilation, or addressing other issues that may be causing dampness in the area. Once the moisture issue has been resolved, the affected wood can be removed and replaced with new, dry wood.

In some cases, a fungicide may also be applied to the surrounding area to prevent further fungal growth.

How dry rot is treated

Dry rot, on the other hand, can occur in much drier conditions and requires a different approach.

Treatment typically involves identifying and removing all of the affected wood, as well as any other materials that may be harbouring the fungal spores. The surrounding area may also be treated with a fungicide to prevent further spread of the dry rot. In severe cases, it may be necessary to install additional ventilation or drainage to prevent future occurrences of dry rot.

Prevent and eliminate rot with Croft Preservation

If you suspect that your home is infected with rot, it's important to have it inspected by a professional and take appropriate measures to remediate the problem. The earlier you get it looked at, the easier it is to treat.

The team at Croft Preservation have been dealing with wet rot and dry rot for nearly 40 years. We’ve handled a range of projects, big and small, everything from a single rotten beam to a whole house infection. We have the hands-on experience needed to deal with any rot problem your home may have.

We follow a step-by-step approach when treating your property. First, we’ll carefully identify the extent of the problem to determine the appropriate course of action. This may involve removing and replacing any rotten wood and improving ventilation in your home to prevent future recurrences.

After we begin working on your property, we’ll use only low-odour and low-hazard HSE products. Our products are also specifically formulated to safeguard your property against any future outbreaks, guaranteeing a long-lasting solution to your problem.

Don’t wait for a small case of rot to become a major headache. Get a quote online or call us on 01202 737739 - we’re happy to answer your questions and explain the process in more detail, so don’t hesitate to reach out today!