Commercial Roof Testing and Inspections
Infrared Moisture Scans, Drone Inspections and Core Sampling
Why Test a Commercial Roof Before You Repair, Coat or Replace It
A commercial roof can look sound on the surface and still hold water in the insulation below. That hidden moisture is one of the main reasons a repair fails, a coating does not last, or a recover is the wrong choice. McGuire Roofing tests commercial roofs so you can see what is happening under the membrane before you spend money on the next step.
We use infrared moisture scans, drone inspections and core sampling to document the condition of the roof, find wet insulation and confirm the layers that are in place. The result is a written report you can use to decide whether to repair, recoat, recover or replace, and to plan the budget that goes with that decision. Depending on the project, testing can be a standalone paid service or part of a roof bid. Ask us which fits your building.
Testing is useful when you are planning a repair or replacement, considering a coating, buying a building, or trying to understand a leak that keeps coming back. We test TPO, PVC, EPDM, modified bitumen, metal and built-up (BUR) roofs on commercial, industrial and multi-family buildings from our base in Knoxville, across Tennessee, and for clients we serve nationally.
We are Johns Manville certified, Duro-Last certified and GAF certified on commercial roofs. Learn more about our commercial roofing work, or request a quote to talk through testing for your building.
Infrared Moisture Scans
An infrared moisture scan, also called a thermal or infrared roof inspection, looks for temperature differences across the roof that can indicate wet insulation beneath the membrane. Wet insulation holds heat differently than dry insulation. After a sunny day, those differences often show up most clearly once the roof begins to cool in the evening, which is why this kind of scan is typically done at night after a day of sun.
We perform infrared scans as walk-on surveys on the roof. We also fly drones equipped with thermal cameras, which is useful on large roofs and in areas that are hard to reach on foot. In both cases, the scan looks for the same kind of temperature differences.
What an infrared scan can find:
- Hidden wet insulation – Damp or wet areas that are not obvious from a visual walk of the roof.
- Travel paths under the membrane – Patterns that suggest water is entering at a seam, flashing, drain or penetration and moving away from the original point of entry.
- The size of the problem – The approximate location and extent of suspect areas, which helps you see whether a condition is limited or widespread.
Infrared scanning is a non-destructive first look. Suspect areas are then checked more closely, and may be confirmed with core samples, so the report is based on more than a thermal image alone. A moisture survey is especially useful before a coating or a recover, because those options generally require a dry assembly. See our commercial roof coatings page for how we evaluate coating candidates.
McGuire Roofing performs moisture surveys in-house. When it is useful, we may also use electronic leak detection to help pinpoint breaches in the membrane. Our commercial roof maintenance programs page describes how moisture surveys fit into ongoing care of the roof.
Drone Roof Inspections
A drone inspection gives you a clear view of the entire roof, including large roofs, high roofs and areas that are difficult or time-consuming to reach on foot. Flights are conducted by an FAA Part 107 certified drone pilot. Our drones carry cameras for standard aerial photographs and for thermal imagery, so a drone visit can document visible conditions and support an infrared moisture scan.
Those photographs and images are useful for:
- Owners and property managers – A complete picture of the roof without walking every section in person.
- Insurance documentation – A dated visual and thermal record after a storm, to go with a closer inspection on the roof.
- Facility managers – A way to plan repairs and compare condition from one visit or one year to the next.
- Buyers and advisors – Documentation of the roof as part of due diligence on a building.
A drone inspection does not replace a hands-on evaluation or a core sample. It is a way to document the roof thoroughly, collect thermal data when a walk-on scan is not the best fit, and direct closer inspection where it is needed. Drone photographs and thermal images can be included in the written report along with on-roof findings.
Core Sampling
A core sample is a small, controlled cut through the roof assembly. It lets us see the layers in place, the type of insulation, whether those materials are wet, and how the roof was built. After the sample is taken, the opening is patched.
Core samples help answer practical questions:
- What membrane, insulation and other layers are on the roof?
- Is the insulation wet, and in which layers?
- Is the roof a candidate for a recover, or does wet material need to come out?
- How many roofs are already on the building?
Building codes generally limit a building to two roofs. If a second roof is already in place, a recover is usually not an option, and a tear-off may be required. Even when only one roof is in place, a recover only makes sense if the existing assembly is dry and sound enough to stay. Core sampling, together with the moisture scan, helps confirm whether a recover is eligible or whether a tear-off and replacement is the sounder path. Local code and the condition of the roof control the final recommendation.
Cores are taken in selected locations, including areas the infrared scan flags as suspect and areas that represent the broader roof, so the findings are not based on a single spot.
What You Get: A Written Report and a Clear Recommendation
After testing, you receive a written report you can share with ownership, a property manager, a buyer or an insurer. Reports generally include:
- Photographs of the roof and of the areas tested, including aerial photos when a drone inspection is part of the work.
- A moisture map or marked plan showing where wet or suspect areas were found.
- Notes on the roof system, the layers confirmed by core samples, and the moisture findings.
- A recommendation on the practical next step: repair, recoat, recover or replace.
- Information you can use to plan a budget and a timeline, instead of guessing at the scope.
For non-emergency work, the written report is typically ready 48 to 72 hours after the site visit. Emergency situations are handled separately. If you have an emergency, call 865-338-7663, answered 24/7.
Depending on the project, testing can be a standalone paid service or part of a roof bid. Ask us which fits your building.
We are the same contractor that can carry out the work, so the people reading the results are the people who will recommend and, if you choose, perform the repair or replacement. You are not required to hire us for the work that follows. The report is meant to give you a clear basis for the decision.
If the right next step is ongoing care rather than a major project, our maintenance programs provide scheduled inspections and documented reporting after the roof is back in sound condition.
Who Commercial Roof Testing Is For
This work is for people who need a documented look at a commercial roof, not just a quick visual walk:
- Property managers – Condition information you can share with owners and use for capital planning.
- Building owners – A clear basis for deciding whether to repair, restore or replace.
- Buyers and advisors – Due diligence documentation when you are purchasing or evaluating a building.
- Facility managers – Help with recurring leaks, coating decisions, or a roof that is nearing the end of its service life.
If you already have a maintenance program with us and need a deeper look than a visual visit can provide, we can add a moisture survey, drone documentation or core sampling to that work.
Roof Systems We Test
We test the low-slope and metal systems common on commercial buildings in this region, including:
- TPO
- PVC
- EPDM
- Modified bitumen
- Commercial metal, including R-panel and standing seam
- Built-up roofing (BUR)
If we did not install the roof, we can still test it. A test is often the right first step on a roof whose history is incomplete.
Commercial Roof Testing and Inspections FAQ
What is a commercial roof moisture survey?
A commercial roof moisture survey finds where water has entered the roof assembly, including wet insulation that may not be visible on the surface. McGuire Roofing uses infrared scanning, performed as a walk-on survey or with a drone equipped with a thermal camera, and confirms findings as needed with core samples. Electronic leak detection may also be used to help pinpoint membrane breaches.
When should I have my commercial roof tested?
Testing is worth considering before a repair, coating, recover or replacement; when you are buying or selling a building; when leaks keep returning after patches; or when you need a documented condition report for budgeting. If you are not sure whether a full test is needed, call 865-338-7663 and we will help you decide.
Does a core sample damage the roof?
A core sample is a small, controlled cut. We take only what is needed to see the layers and check for moisture, and we patch the opening when we are finished.
Can testing tell me if my roof can be coated or recovered?
That is one of the main reasons to test. Coatings and recovers generally require a dry, sound assembly, and a recover also depends on how many roofs are already in place and on local code. The moisture survey and core samples help show whether those options are realistic or whether repair or replacement is the better path.
Do you use drones for commercial roof testing?
Yes. An FAA Part 107 certified drone pilot can document the roof with aerial photographs and thermal imagery. We also perform infrared scans as walk-on surveys on the roof.
Do you test roofs you did not install?
Yes. We test commercial roofs regardless of who installed them.
How soon will I receive the testing report?
For non-emergency work, the written report is typically ready 48 to 72 hours after the site visit. Emergency situations are handled separately. Call 865-338-7663 if you need help right away.
How much does commercial roof testing cost?
Depending on the project, testing can be a standalone paid service or part of a roof bid. Ask us which fits your building. Call 865-338-7663 or request a quote.
Schedule a Commercial Roof Test
Call 865-338-7663 (answered 24/7) or request a quote online, and we will talk through infrared testing, drone inspection and core sampling for your building. You can also see our commercial roofing services. Financing is available for repair or replacement work that follows.
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