Finding the wet insulation before pricing the roof.

On a low-slope roof, most of the money is under the membrane. Wet insulation has to come out; sound insulation can often stay. Whether a project removes a tenth of the assembly or all of it is usually decided by an assumption, and a moisture survey is how that assumption becomes a map that two contractors can bid against.

Compare this on your roof

A low-slope commercial roof at dusk, mechanical curbs silhouetted against a warm horizon.

At a glance

The system, before the sales pitch.

Specification first. Every row below is a property of the system, not a claim about a product line.

Why it changes the number: Tear-off and disposal of saturated insulation is among the larger variables in a low-slope replacement, and it is invisible from above. A survey converts it from an allowance based on nothing into a marked area with a measurement behind it, which is the difference between comparable bids and a guessing contest.
Infrared: Wet insulation retains heat and releases it more slowly than dry insulation, so scanned after sunset on a clear day the wet areas read warm. It needs a dry surface, a clear sky, a genuine temperature drop, and an assembly that transmits the difference. Ballast, some cover boards and certain systems defeat it entirely, and it is honest to say when conditions were not suitable.
Capacitance and nuclear meters: Handheld readings taken on a grid across the roof. Faster to run and far less dependent on weather than infrared, and they produce comparative readings rather than a picture. Useful to confirm and bound an infrared result, and useful on the many roofs where infrared conditions are not going to occur on the schedule available.

A low-slope commercial roof field with mechanical curbs, a drain and welded seam lines.

How the system behaves

Performance is an assembly, not a product name.

A metal equipment curb on a granulated cap-sheet membrane roof, the membrane flashing dressed up the base of the curb.

Core cuts settle it

A small cut through the full assembly, examined, photographed and patched before the crew leaves the roof. It is the only method that establishes what the layers actually are, how thick they are, how many roofs are already up there and whether the material is wet. Every other method is an indication until a core confirms it.

The map is the deliverable

Areas marked on a roof plan, tied to photographs, with the method stated and the conditions it ran under recorded alongside it. That is what a design or a bid gets priced against, and it is what makes two proposals for the same building comparable to whoever has to choose between them.

What a survey does not determine

It describes moisture in an assembly on a date. It does not determine what caused the moisture, apportion responsibility between parties, or establish what any of it means under a policy or a lease. Those are separate determinations made by other people, and a contractor's survey should not be presented as any of them.

Choose a starting point

Match the next step to the condition.

A short, non-diagnostic guide for working out what kind of assessment conversation to prepare for.

What best describes the property today?

Decision support

Choose a starting point.

Four situations, and the sensible next move for each. It does not diagnose a roof, decide insurance coverage, or stand in for somebody looking at the property.

What the next step actually is
What to have ready before anyone arrives
What we will not ask you to do

Questions

Useful answers, without overpromising.

Do we need a moisture survey before replacing a roof?

On anything beyond a small area it usually pays for itself in the bidding alone, because it removes the largest unknown from every proposal. It is most valuable where the building has a leak history, where previous repairs are visible, or where an assembly of unknown age and construction is being priced.

Will core cuts damage the roof?

A core is a small opening cut and patched on the same visit by the people who made it, and its location is recorded. The information it produces about what is actually in the assembly is not obtainable any other way, and on an unknown roof it is generally worth the openings.

The infrared scan found nothing. Does that mean the roof is dry?

Only if the conditions supported the method. Without a dry surface, a clear sky and a real temperature drop, a negative result is not a result. A survey report should state the conditions it was carried out in so that its own findings can be weighed properly.

Should the survey be run by the contractor bidding the work?

It is worth thinking about, because the party that maps the wet insulation is also the party whose scope grows with it. A survey commissioned independently, or run by one party and confirmed by cores everybody can look at, removes that tension. At minimum ask for the method, the conditions it ran under and the marked plan, so that the result can be checked rather than simply trusted.

Assessment request

Tell us what is happening at the property.

Short, routing-only questions. Nothing here asks you to diagnose the roof yourself.