As stated, there are numerous types of Wet Rots, which are divided into various categories. We’ll stick to the most popular one which is referred to as "The Cellar Fungus" (Coniophora puteana). Whilst there are certain aspects of this fungus that are similar to Dry Rot it behaves in a much different manner although the end result can be nasty.
The olive brown fruiting body with its white margin is not always seen in the area of broken down timbers. The mycelium can usually be found and will appear as dark thread or even as thick as shoe laces (as seen on the left hand side of (Fig 3a). It can also appear in a white fan-like shape, usually found under linoleum or other floor coverings as seen on the right hand side of (Fig 3a). This disguise is often confused with the dry rot mycelium.
Other characteristics such as "Cubing or Cracking" of the wood are similar but different to the dry rot if a closer look is taken. The cubes and cracking of the wet rot are usually smaller and the timber darkens in colour unlike the dry rot where the cubes and cracks are usually larger and wider and the timber ends up lighter in appearance and weight (Fig 3b).
The wet rot attack can be just as destructive as the dry rot as seen in (Fig 3c). One of the main differences between the two rots is the amount of moisture required for them to maintain activity and feed. Wet rot requires a moisture content of at least 30%+, where as the dry rot can survive between 22% - 30% on average. Hence the reasons for the names!
Treatment - While the treatment for wet rot is not as intense as that required for dry rot, careful measures must still be taken. If a bit of forethought is applied, eradication can be achieved without, or at least minimal chemical application.