A few facts about Dry Rot:

• Dry rot is the common name for wood destroying fungus and despite its common name ir will generally attack damp timber.
• Dry rot will only affect timber that is damp, typically affecting timber with a moisture content in excess of 20%.
• Wood needs 4 things to decay; water, oxygen, food (wood), and favorable temperatures (40F – 015F).
• It is essential to understand that water is fundamental to the growth and survival of not only dry rot but all wood destroying fungi; wood decay cannot occur, exist or survive without it!
• Not all wood, wood siding, wood decking and wood trim made from cedar, redwood or other species famous for durability are if fact rot or decay resistant . As a side note termites will eat cedar, I’ve seen them in mulch.