What is a key requirement for a wood foundation using lumber treated according to AWPA standards?

A key requirement for a wood foundation that utilizes lumber treated according to AWPA (American Wood Protection Association) standards is that it must be treated in accordance with AWPA C22. This standard provides specifications for wood used in foundation systems, ensuring that the lumber is adequately treated to resist decay, insects, and other environmental factors that could compromise its structural integrity.

AWPA C22 refers specifically to the types of pressure treatments and preservatives appropriate for use in foundations, which is crucial for maintaining safety and longevity in construction. Adhering to these standards ensures that the wood foundation will withstand the conditions it encounters, particularly when it is in contact with soil or moisture, which are factors that can lead to deterioration if not properly managed.

The other options present different scenarios that do not align with the established AWPA guidelines or practical applications for wood foundations. Submerging the foundation completely in water or ensuring it does not touch the ground are not standard requirements for wood foundations: materials are designed to handle moisture but are not meant to be submerged. Painting with a waterproof finish can provide additional protection but is not a core requirement outlined in the AWPA standards for wood treatment.