Interior floor soft spot (water damage)

A soft spot in the floor almost always means water intrusion has been happening for a while, even if you never noticed an active leak — it tracks along the subfloor before showing up as softness. The real work isn't patching the soft spot, it's finding where the water is actually getting in, which is often nowhere near where the soft spot appears since water travels along framing before pooling. Roof, windows, and slide seals are the top three sources to check first. Where's the soft spot located relative to windows, roof penetrations, or slides?