Can termites damage flooring or wall supports?

This is a case where the common claim gets the facts right. Sill plates, floor joists, subflooring, and wall studs near soil contact are exactly the building elements subterranean termites attack, because the colony originates in the ground and tunnels upward, building mud tubes to bridge any exposed gap like a foundation wall on the way to accessible wood. There's no need to soften this answer — floors and wall supports genuinely are the parts of a house most exposed to termite feeding.

Termites feed along the wood grain from the inside, often leaving a thin, largely intact outer shell while hollowing out the interior — which is exactly why a floor can feel spongy or a joist can sound hollow when tapped well before any obvious visual damage appears from the outside. That internal, hidden progression is part of why this pest earns real concern: the damage can be substantial before it's discovered through casual observation alone, which is why probing and professional inspection matter more than a visual walkthrough.

The one place marketing language distorts this otherwise accurate picture is timing. Phrases implying floors could give way or wall supports could fail in short order overstate how fast subterranean termite damage actually progresses. NC State Extension's figure — three to eight years of ongoing, untreated feeding before serious structural damage occurs — is the honest clock, and New Hampshire's cold winters slow termite activity for a meaningful part of each year on top of that baseline.

That correction isn't a reason to dismiss the risk; it's the reason there's real time to catch it. Mud tubes on a foundation wall, discarded swarmer wings near windows, or a joist that sounds slightly hollow when tapped are all signs worth investigating well before a floor becomes visibly compromised — and because the target list here is accurate, those signs deserve to be taken seriously rather than second-guessed.