Dry and Wet Rot

Excessive moisture, from a flood, leak or defective guttering can cause timbers to rot, for example. Rot can also occur when timbers are in contact with damp walls due to lack of ventilation or lack of an effective damp proof course, for instance. It is usually found in hidden unventilated voids where timbers are present.

Wet rot stays localised to the source of moisture and the timber is wet in appearance. It will also show signs of shallow cuboidal cracking on the timber surface. Dry rot can grow far from the source of the moisture with evidence of a white/grey coloured growth over the timber. There are often signs of a white mushroom-like growth, known as a fruiting body, which expels reddish/brown spore dust into the surrounding area. The timber shows signs of larger cuboidal cracks more deep-seated than that of wet rot.

Dry rot is a wood destroying-fungus which feeds on moisture in timbers. Dry rot spores, which are always present in the atmosphere, land on timber, and in the correct environmental conditions will germinate and produce hyphae (fine strands of fungal growth). These hyphae strands join together to form a mass called Mycelium which can vary in colour from grey to pure white, and these strands grow into and across the damp wood. It can also grow into materials such as plaster, mortars, bricks etc. When the growth is advanced a fruiting body (Sporophore) may develop. This fruiting body takes the form of a “fleshy pancake”, the surface of which is orange/ochre coloured. A large numbers of spores generate from the centre of the fruiting body, under still conditions, and form the red “dust” often visible where there is a significant attack of dry rot.

It is not always possible to provide any cost of treatment until the full extent of the problem is identified. To do this, we would have to carry out a full survey before we could provide a quotation. We do provide a fixed price quotation for all identified and listed works, as stated in our report. However, as dry rot can spread to other areas not evident at the time of inspection, we recommend a full exposure survey be carried out to all adjoining areas to avoid unforeseen additional works and costs.

In general, we may have to remove the affected floor and joinery timbers, sterilise the masonry and then replace the joists, floorboards, skirting boards etc. However, every property is different and therefore so is every specification, as many factors have to be taken into account such as the severity of the attack and how easy it is to gain access to carry out the dry rot treatment.

Most work carried out will only cause minor disruption to the home owner, however this will depend on the extent of the damage, but vacating the property is uncommon.