What causes dry rot?

Dry rot in timber occurs when airborne dry rot spores come into contact with wet timbers. The spores germinate on those timbers which have a moisture content in excess of 28%, but best thrive when with levels are between 35 – 45%. The most common cause of dry rot in timber is blocked sub floor vents, timbers being in contact with damp masonry and from leaking pipe work. This prevents moisture under the property being ventilated. Although timbers which are treated with preservatives are at lower risk of fungal decay, dry rot has been known to attack and grow over these.

As dry rot in walls and under floorboards grows, it develops fruiting bodies. These are easily identifiable due to their rusty orange coloured fleshy structure and paler margins. Once matured, the fruiting bodies produce more rot spores which can spread over vast distances as they travel through the air.

What does dry rot look like?

Dry rot is fortunately fairly easy to identify but can commonly be misdiagnosed as other types of rot. If you have any of the following symptoms present, we recommend you contact Prokil so that one of our experts can attend to carry out a survey to determine the type of treatment you require for dry rot.

• Sheet like growth of mycelium, strands or fruiting bodies.
• Large cuboid cracking of timbers
• Musty odour; mushroom/ mouldy smell
• The appearance of shrinking sections of skirting boards
• Springy sections of floors
• Timbers which easily break or crumble