Roof Flashing Inspection Field Guide: What to Check, Leak Clues, and Report Language
Most roof leaks are flashing problems, not “bad shingles.” Flashing is where the roof system transitions: walls, chimneys, skylights, valleys, and penetrations.
This field guide is built for inspectors: fast checkpoints you can document from the ground, ladder, attic, and roof (when safe), plus language that stays observational and defensible.
Important
Roof access is a safety decision. If conditions aren’t safe (pitch, height, wet surfaces, brittle covering, limited access), document the limitation and recommend qualified roofing evaluation.
1) Start With the Leak Clues (Even If There’s No Active Leak)
Before you focus on one flashing detail, scan for:
- Stains at ceilings/walls under roof intersections and around chimneys/skylights
- Attic staining at sheathing/rafters near valleys and penetrations
- Rusty nail tips and darkened wood at roof decking (moisture history)
- Granule loss patterns near valleys/sidewalls (can indicate water pathways)
2) Flashing Locations You Should Always Check
Sidewall / step flashing
Where a sloped roof meets a vertical wall (dormers, second-story walls, additions):
- Missing step flashing
- Step flashing buried behind siding with no visible evidence (limitations)
- Caulk used as the primary “seal”
- Deteriorated siding/fascia near the intersection
Kickout flashing
At the bottom of a roof-to-wall intersection where water needs to be directed into a gutter:
- Kickout missing (common)
- Evidence of rot/staining at wall below the intersection
Chimney flashing and counterflashing
At masonry chimneys, you often see:
- Loose, missing, or damaged counterflashing
- Step flashing defects where chimney meets roof plane
- Excessive sealant patches
- Mortar joint issues where counterflashing is embedded
Plumbing vent boots / penetrations
Look for:
- Cracked/deteriorated rubber boots
- Improperly sealed fasteners
- Lifted shingles around the boot
- Rust streaking or staining below the penetration in attic
Valleys
Valleys handle concentrated water flow:
- Debris buildup (leaves, granules) holding moisture
- Exposed fasteners where they shouldn’t be
- Deteriorated metal valley lining
- Shingle valley cuts that look irregular or “repaired”
Skylights
Common issues:
- Improper flashing kits
- Sealant-only repairs
- Staining at skylight curb (interior) or surrounding sheathing (attic)
3) Quick “What You Can Document” Checklist
During an inspection, you can usually document:
- Flashing present/visible vs not visible due to coverings/height/limitations
- Sealant-heavy repairs (a clue that flashing may be compromised)
- Obvious gaps, lifting, rusting, or missing sections
- Moisture evidence inside (attic/interior finishes)
- Whether gutter/downspout routing increases overflow risk at roof-to-wall intersections
Note
Avoid declaring the exact leak source unless it’s directly observable. It’s safer to document the most likely contributors and recommend qualified evaluation/repair.
4) Photos That Make Your Write-Up Strong
- Wide shots showing the roof plane + intersection (wall, chimney, valley)
- Close-ups of boots, joints, sealant repairs, lifted materials
- Interior/attic photos of staining aligned with the exterior location (when possible)
- Any rot, damaged siding, or peeling paint below roof-to-wall intersections
Report Language Templates
General flashing concern
“Defects were observed at roof flashing/penetration(s) (____). Flashing defects are common leak sources. Recommend evaluation and repair by a qualified roofing contractor and re-check after the next rain event.”
Kickout flashing missing / wall damage risk
“Kickout flashing was not observed at the roof-to-wall termination point (____). This can allow water to run behind siding and cause rot. Recommend correction by a qualified roofing contractor.”
Vent boot deterioration
“The plumbing vent flashing boot appears deteriorated/damaged (____). This condition can allow water intrusion. Recommend roofing contractor repair/replacement.”
Limitation (no roof access)
“Roof surface access was limited/unsafe at the time of inspection (____). Flashing conditions could not be fully evaluated. Recommend qualified roofing evaluation as needed.”
Where ReportWalk Helps
Flashing findings live or die on location detail (“dormer right sidewall above garage”, “chimney cricket area”, “rear valley at addition”). ReportWalk helps you capture those specifics in the moment — voice + photos — and produces clean narratives without vague, hard-to-defend wording.
