Most contractors say “thorough inspection” and leave it there. Here is the actual list — what we work through, which parts only happen sometimes, and what you get at the end.
A commercial roof inspection should cover six areas: the membrane surface itself, every place the roof is interrupted, the drainage path, what sits underneath, the equipment on top, and the paperwork. A few scanning diagnostics sit outside that list and are performed only when the surface suggests they are needed. At the end you should receive a written report with photographs, findings, and prioritized recommendations — not a verbal summary and a quote.
Here is what each part is actually looking for.
The surface and its seams
The membrane gets checked for blisters, punctures, tears, cuts, abrasions, ridging and general wear. Seams and overlaps are inspected for openings, loose laps, inadequate seals and any sign of separation or deterioration.
On modified bitumen or shingle roofs, granule loss is assessed for what it means for UV protection and membrane exposure. Walkway pads and protective surfacing are checked for wear and proper placement. And debris gets noted — leaves, branches and dirt impede drainage, damage the membrane, and encourage biological growth.
Every place the roof is interrupted
This is where roofs fail, so it carries the most checks.
Flashings — base, counter and termination bar, examined for damage, corrosion, secure attachment and proper sealing
Penetration flashings — around pipes, vents, HVAC units, skylights and hatches, checked for watertight seals and signs of wear
Coping and parapet walls — metal, stone or masonry, examined for cracks, displacement, damage and water infiltration points
Sealants and caulking — at penetrations, flashings, joints and terminations, inspected for cracking, peeling, voids and deterioration
Fasteners — checked for looseness, corrosion, backing out or absence on mechanically attached systems, where accessible
Flashing at a curb penetration. Details like this one are where most commercial roofs actually begin to fail — not in the open field of the membrane.
Where the water is supposed to go
Gutters, downspouts, scuppers and internal drains are evaluated for blockages, damage, flow, secure connections and adequate capacity. Ponding water is identified and documented, with an assessment of its potential for long-term membrane degradation and structural impact. Roof vents — static, mechanical, intake and exhaust — are checked for airflow and for moisture building up inside the roof assembly.
Ponding water. We document where it collects and how long it stays, because standing water accelerates membrane degradation.
What is underneath
Where the substrate is visible or accessible, it is examined for rot, moisture damage, sagging and other deterioration in the deck. Previous repairs are evaluated for condition, integrity and whether they actually worked. And accessible interior ceilings and walls directly beneath the roof are checked for active or past leaks, water stains and moisture damage — because the inside often tells you something the surface will not.
The equipment and the hazards
Rooftop equipment — HVAC units, solar panels — is inspected for condition and mounting, the integrity of its flashings, and its impact on the roof. Immediate safety concerns are identified as well: unsecured equipment, trip hazards, electrical issues.
The paperwork most people do not expect
Two of these involve no climbing at all. The roof warranty is reviewed against what is actually on the roof — coverage, exclusions, and anything observed that could affect its validity. And the system gets a building code compliance overview for general conformance with current requirements.
The checks that only happen when warranted
Not everything happens on every inspection, which is worth knowing before you compare one contractor’s inspection to another’s.
Infrared thermography scan — a thermal scan detecting moisture trapped beneath the roof surface that is not visible to the naked eye
Core sampling — cutting into the assembly to verify its layers and identify internal moisture or deterioration
Roof MRI moisture scan — mapping the roof so saturated areas can be measured and located rather than estimated
Each is performed when what we see on the surface suggests there is something below it. A few of the routine checks carry conditions of their own: granule loss applies only to certain systems, and fasteners and substrate are examined only where they can actually be reached.
What a visual inspection cannot tell you
A person walking your roof can see the surface, the details and the drainage. What they cannot see is water sitting inside the assembly. Insulation holds moisture without producing any surface symptom, which is why a roof can look acceptable from above and still be saturated underneath.
That is the entire reason the scanning steps exist as separate, conditional items rather than standard ones. If the visual inspection turns up nothing concerning, adding them costs you money to confirm what is already apparent. If it turns up ponding, prior repairs of unknown quality, or interior staining that does not match anything visible above, then the visual inspection has done its job — by telling us it cannot answer the question on its own.
So a clean inspection report is not a guarantee that a roof is dry. It is a statement that nothing visible suggests otherwise. Anyone who tells you differently is overselling what a walk on a roof can do.
What we do
We start by asking what you have noticed and reviewing whatever history the roof has — a stain you have been watching for six months changes where we look first. Then the systematic on-roof evaluation, guided by our checklist, with the scanning diagnostics added only if what we find calls for them.
You get a written report with photographs, the overall condition of the roof, and recommendations in priority order. If the answer is that your roof is fine and you should call us in a year, that is what the report will say. We would rather tell you that than manufacture a reason to be back next month.
Ready for a clear view of your roof’s condition?
We will walk it, document it, and tell you plainly what we find.
