Which building code must the under-floor space meet when wood decay fungi are present in the crawl space?

The correct choice is the International Residential Building Code, which sets forth regulations to ensure the safety and health of occupants in residential buildings. When there is a concern about wood decay fungi in the crawl space, the code provides specific guidelines on how to address and mitigate potential problems associated with moisture and structural integrity.

Adhering to the International Residential Building Code is crucial because it includes provisions for proper ventilation, drainage, and other measures that prevent moisture accumulation, which is essential in preventing wood decay and ensuring the overall stability of the structure. This code is widely recognized and adopted in many jurisdictions, making it the applicable standard for addressing issues like wood decay fungi in residential settings.

While local codes may also contain relevant regulations, they often derive their standards from the International Residential Building Code. The National Building Code is more general and usually applies to commercial buildings, while the Environmental Protection Code typically deals with broader environmental issues rather than specific building construction and maintenance practices.