Commercial Roof Inspection Checklist

Before you climb

• Pull the original roof specs, age, and any warranty documents.
• Review the prior inspection report. Note what was flagged.
• Check the weather. Walk dry roofs only. Wet membranes are slippery and easier to damage.
• Bring: notepad, camera, probe rod, knee pads, soft-soled shoes, and harness for fall protection where required.

Membrane surface

• Cracking, splitting, or alligatoring across the field.
• Blisters or pillows under the membrane.
• Granule loss (modified bitumen).
• Punctures, abrasions, or cuts from foot traffic, tools, or hail.
• Discoloration or staining suggesting chemical exposure.
• Membrane shrinkage at corners and perimeters.

Seams

• Lifted edges, fishmouths, or visible separation.
• Compromised seam tape on EPDM.
• Cold welds or open seam ends on TPO and PVC.
• Probe each suspect seam with a dull tool. A good seam will not lift.

Penetrations

• Every pipe boot for cracking, sun damage, or pulled-loose flashing.
• HVAC curbs for sealant failure and lifted flashings.
• Vents, skylights, and conduit penetrations.
• Roof drains, scuppers, and overflow scuppers for blockage and damaged flashing rings.

Flashings and edge details

• Parapet wall flashings: membrane, coping, and counterflashing.
• Termination bar fasteners and sealant condition.
• Edge metal: lifted seams, missing fasteners, corrosion.
• Through-wall flashings at expansion joints.

Drainage

• Standing water more than 48 hours after rain.
• Clogged drains, scuppers, or downspouts.
• Damaged or undersized drain bowls.
• Granule, leaf, or trash buildup in low spots.
• Gutter condition: slope, fasteners, leaks at corners and downspouts.

Rooftop equipment

• Loose or unsecured equipment vibrating on the membrane.
• Refrigerant lines crossing the roof without supports.
• Walk pad coverage on common access paths.
• Antenna mounts, satellite dishes, and conduit supports.

Underside (where accessible)

• Staining on ceiling tiles or interior deck.
• Rust, sagging, or moisture on the underside of metal deck.
• Saturated insulation visible from cut openings.
• Odor of mold or wet drywall.

Documentation

• Date-stamped photos of every flagged area.
• Marked-up roof plan showing locations of issues.
• Severity classification: monitor, repair this year, urgent.
• Estimated repair budget by category.
• Next inspection due date.

When to inspect

Spring after the last hard freeze and fall before the first snow are the two essential windows. Add an inspection after any storm with hail, sustained winds over 60 mph, or unusually heavy rain. Buildings under manufacturer warranty almost always require documented annual inspections at minimum.

Indiana-specific notes

Our climate punishes commercial roofs differently than the Sun Belt. Freeze-thaw cycles attack any small breach. Heavy spring rains expose drainage problems. Late summer thunderstorms test seam integrity. A spring-and-fall cadence is the minimum, not the ideal.

Related reading

• Commercial Roof Maintenance Guide
• Signs Your Roof Needs Repair
• Full Building Maintenance Checklist