What must a foundation wall or floor include if it is in contact with the soil?

Foundation walls or floors that come into contact with soil must include a vapor barrier and termiticide to ensure proper moisture control and protection against termites. A vapor barrier is essential as it prevents moisture from the soil from penetrating into the structure, which can lead to issues such as mold growth, deterioration of materials, and compromised structural integrity.

Termiticide is important because it serves as a chemical barrier that helps to protect the building from termite infestations, which are a significant risk for structures built near or in contact with soil. By implementing these measures, builders can significantly reduce the risk of damage caused by moisture and pests, creating a more durable and resilient foundation for the building.

While other options may address various aspects of building design or site management, they do not specifically address the critical needs of moisture control and pest prevention in contact with soil.