Commercial roof inspections: what they cover and how often

A commercial inspection answers a different question

On a house, the question is usually repair or replace. On a commercial or multi-family building it is closer to asset management: what is the condition, what will it need in the next two years, and what is the cost of doing nothing. The report has to be usable by someone approving a budget, not just by whoever is on site.

That changes what gets recorded. Condition per area rather than one verdict for the whole roof, photographs tied to locations, and a distinction between what needs doing now and what can be scheduled.

Flat roofs fail at the details, so that is what gets checked

The field of a membrane roof is rarely the problem. Failures start at the seams, at terminations where the membrane meets a parapet or wall, at penetrations for vents, drains and old antenna mounts, and wherever water sits instead of draining.

So a real inspection walks the seams and the perimeter rather than looking across the roof from the hatch. Ponding water days after rain gets noted, because it points at either the fall or a blocked outlet — and only one of those is fixed by new membrane.

How often, realistically

Twice a year is the standard recommendation and it is a reasonable one: once after winter, once before it. In Maryland the winter check earns its keep, because freeze-thaw cycling is harder on seams and flashing than the temperature alone suggests.

Add a check after any significant storm, and after any work by another trade. A surprising share of the commercial leaks we are called to were made by an HVAC or telecoms contractor who went up, did their job, and left a penetration behind them.

What the report should contain

Photographs tied to locations rather than a folder of anonymous close-ups. Condition by area. Drainage assessed, including outlets and scuppers. A separation of urgent work from scheduled work. And a plain statement of what happens if nothing is done, because that is the part a budget holder actually needs.

What it should not contain is a single replacement price with no supporting detail. A commercial roof rarely needs replacing all at once, and a quote that assumes it does is usually easier to write than to justify.