True Dry Rot fungus is a rapidly spreading and serious form of attack on timber. It requires a moisture content in wood of 20-25% and, in conditions of poor ventilation, can spread its fine grayish threads many feet in just a few months.
Attacks are often concealed behind brickwork and plaster – becoming well established before visible evidence appears.
Attacked wood becomes discoloured and brittle, and as it dries out will eventually crumble into dry brittle blocks.