Dry Rot

What Is Dry Rot ?

Dry rot is a previous term used to describe timber decay as a result of wood destroying fungi.

Serpula Lacrymans, the name given to the fungi, appears in most parts of the world. Although it affects natural living forests, Dry rot is best known for its ability to destroy timbers in olden day ships neutralizing whole fleets.

Unlike Wet Rot, Dry Rot can germinate and grow at low level moisture contents, any unprotected timber with a moisture content above 20% is at risk of a fungal attack. Once the fungi begins to grow over time it will destroy the natural characteristics of timber, causing a dark coloured, chequered and cracked appearance resulting In the timber eventually crushing into powder.

What Causes Dry Rot ?

Dry rot can occur in any property type when unprotected or untreated timber becomes damp.

Usually the most common reason for the dry rot fungi to grow is property defects such as leaking pipes, penetrating damp, and rising damp which can all cause the moisture content of the timber to exceed 20%, the ideal starting point for timber decay.

The lifecycle of dry rot can be broken down into four main stages. Dry rot begins as a microscopic spore which, in high enough concentrations, can resemble a fine orange dust. If the spores are subjected to sufficient moisture, they will begin to grow fine white strands known as hyphae. As the hyphae germinate, they will eventually form a large mass known as mycelium. The final stage is a fruiting body which pumps new spores out into the surrounding air.

How To Treat Dry Rot ?

Dry Rot should be treated with extreme caution as failure to eradicate all the infestation can cause significant instability in any structure the fungi attaches itself to. As with any fungi attack the first step is to identify the starting point, the cause of any timber becoming damp. Once this is corrected all affected timber should be removed and replaced with a pre-treated timber.

Diagnosing the correct type of rot is essential, although comparisons can be drawn on both sides with the dry/wet rot name, it stops there. Dry rot has the ability to travel through building materials other than wood, masonry being one of them. Any plaster work within the affected area should be inspected making sure no strands have spread beyond the affected area. Additional measures such a masonry irrigation are carried out if this is found to be the case.

Although every measure should be taken to make sure any timber remains damp free, this is not always possible or foreseen. Therefore, we advise secondary measures such as Tribor Gel, A special boron based, brush able and injectable gel for use in high risk areas to treat against dry and wet rot as well as wood destroying insects.

How To Tell Wet/Dry Rot Apart ?

Wet rot and Dry rot are two different types of fungi, Establishing the type of fungi attack in which a property is suffering from is the first step of any successful eradication process. One of the main differences between wet rot and dry rot is that wet rot needs a higher moisture content for the fungi to grow and remain active, usually of around 50% whereas dry rot will grow on any unprotected timber with a moisture content above 20% percent.

Some tell tale signs of Dry rot are:

Orange, Fleshy looking pancakes, (known as the fruiting body).
Cracked, dark brown and chequered looking timber
Damp, moist smell of timber.
Fine fluffy white strands known as mycelium spreading across the timber.
Orange dust, rusty look.

Here at Leodis Damp Control we are always willing to help solve any problems you may have, or answer any questions you need answers for, please do no hesitate to contact our team, we will do our best to help.

Wet Rot

Wet Rot is another wood destroying fungi, sharing some similarities to dry rot, although still very different. To any untrained eye it can be extremely difficult to establish what kind of fungi attack you are suffering from. Read more on Wet Rot to learn a better understanding.

What is wet rot ?