Dry rot is a type of wood decay caused by certain fungi, primarily the species Serpula lacrymans. It thrives in damp, poorly ventilated areas, where it breaks down the cellulose in wood, leading to structural damage. Unlike wet rot, dry rot can spread through the air and can affect wood even if it appears dry on the surface. The signs of dry rot include a musty odor, cracks in the wood, and a powdery residue. To prevent dry rot, it is essential to maintain proper ventilation, control moisture levels, and promptly address any water leaks in buildings or structures.