Typical signs
- A deck that bounces unusually or a guardrail that deforms under moderate push.
- Corroded bolts, missing blocking, split wood or improvised anchors.
Where it is often found
- Decks attached to the house, exterior stairs and guardrails.
What it can mean
- Improper fasteners, rotten wood, excessive spans or inadequate ledger/flashing detail.
What to check next
- Check support, anchorage, bracing, drainage and wood condition.
- Document any deformation, cracking and corrosion.
Reasonable immediate actions
- Limit access and loading if stability is uncertain.
When to stop and call a professional
- Any loose guardrail, suspect ledger, rotten post, hidden attachment or partial failure requires qualified correction.
Prevention
- Compatible fasteners, maintained flashing, drainage, seasonal inspections and reasonable loading.