What moisture content indicates a structure is in need of attention due to potential dry rot risk?

A moisture content of 20% is significant because it indicates an environment conducive to the growth of mold and other fungi that can lead to dry rot, particularly in wood-based materials. Dry rot is a fungal decay that thrives in damp conditions, and moisture levels above 20% are typically considered risky in terms of structural health.

When moisture in a building material, especially wood, exceeds this threshold, it can prompt serious issues such as deterioration of structural integrity, as fungi can begin to decompose the material. Therefore, a measurement at 20% or higher necessitates immediate attention to prevent further water damage and the development of dry rot. Regular monitoring and maintenance of moisture levels are key to ensuring a structure remains sound and free from such potential hazards.