Dry rot also called brown rot is a wood destroying fungus. This develops when excess moisture builds up on wood and the decay weakens the wooden structures inside or outside of your home. If the humidity conditions are right dry rot can spread rapidly. Left untreated, it could compromise the structural integrity of the home.
Check around windows, trim, doors & siding for any surfaces that feel damp or have cracks which can allow water to work its way into the wooden material, resulting in rot.
Examine siding around & beneath the windows for signs of swelling or discoloration. The wood should be firm and hard. If the screwdriver sinks into the wood, you’ve got a wood rot problem.
If the floors feel "bouncy" this a can be a sign of rotten or damages joists. Also, be sure to check for sunken, sagging floors or shrunken wood.
Examine the affected wood for flat skin-like growth which may resemble the outside of a mushroom with shades of silver and gray. This is a wood rot fungus.