The short answer

Look at the ledger as both a water-management detail and a load-bearing connection. A deck may feel solid while water has entered behind the ledger. The useful inspection question is not “where can I add caulk?” but “how is water shed above, behind, and below this connection, and is the wood still sound?”

Visual checks

Area Record Why it matters
Top of ledger Flashing visible, tucked, damaged, or absent Water can enter at the upper edge.
Ledger-to-wall joint Gap, movement, sealant, or staining A gap may reflect structural movement.
Fasteners Pattern, corrosion, withdrawal, and washers Fasteners transfer load and can admit water.
Joist ends Darkening, softness, or exposed cuts Wet ends can hide decay.
Interior wall Staining, odor, or dampness near the ledger Exterior symptoms may already be inside.

Do not remove structural fasteners or climb an unstable deck for a better view. Photograph from a safe position and note whether the deck is attached to masonry, siding, brick veneer, or another unusual assembly. Those conditions change the repair method.

Repair-scope questions

Ask whether the estimate includes deck removal, siding or trim removal, flashing integration, damaged sheathing or ledger replacement, fastener specification, joist-end treatment, and permit or inspection requirements. A surface sealant line should not be priced as equivalent to rebuilding a compromised connection.

Limits

This is a visual planning aid, not a structural inspection or deck design. Movement, rot, or uncertain attachment should be assessed by a qualified professional.