Wood at the base of a post is soft and crumbles when probed. What does this most likely indicate?

Sound wood resists a probe; wood that crumbles under one has lost its structure, and in a building that almost always means fungal decay driven by sustained moisture. The location is diagnostic in itself: the base of a post is where water arrives and stays — from a slab that wicks moisture, from splash, from a leak above running down the post, or from direct contact with soil. Decay at the base is also the worst possible place for it, because that is where the post's entire load is transferred to its support, and a post with a compromised base can lose bearing suddenly. The inspector's job is to report the decay and the moisture source, since repairing the post without correcting the source guarantees a repeat. Probing at bases, sill plates, and beam ends is standard practice for exactly this reason.

Wood that is soft and crumbles under a probe has lost its structure to fungal decay, and the base of a post is where sustained moisture accumulates from the slab, splash or a leak above.

Fungal decay requires sustained moisture and destroys wood structure, leaving material that is soft and crumbles under probing. Post bases, sill plates and beam ends are common locations because moisture accumulates there.

Soft Means Rot, Not Weather. Weathering is skin deep; decay goes all the way through.

Report both the decay and its source. Replacing the post without correcting the moisture guarantees the same finding next time.

• •Reading soft wood as surface weathering
• •Reporting the decay without identifying the moisture source
• •Not probing post bases and sill plates routinely