Infrared Roof Moisture Survey in Kenosha, WI

How the Scan Works

Wet insulation holds heat longer than dry. After a sunny day, a low-slope roof stores warmth, and when the sun sets the dry areas cool faster while the wet ones stay warm. An infrared camera records that difference as a pattern on the roof. We scan in the evening, on dry days, after a stretch of sun, when the contrast is strongest, and we log wind, temperature and cloud cover so conditions can be repeated.

Roof color, surface debris, ballast and rooftop equipment can create false readings. A dark patch of shading may look like a wet area, and a white membrane may mask one. That is why every anomaly is verified by hand. We do not issue a map built from images alone.

The scan can be done on foot or from a drone, depending on the size of the roof. Where a roof covers a wide building, as in a business park like Pleasant Prairie's LakeView Corporate Park, aerial thermal capture followed by ground verification suits the job.

Core Cuts and Meter Readings

The core cut is the proof. We cut a small circular sample through the membrane and insulation at locations the scan flagged and at a few the scan called dry, which acts as a control. Each sample is photographed, measured and assessed for moisture, and the hole is sealed the same day with a compatible patch.

The cores tell us things the image cannot: the number of layers, the type and thickness of the insulation, whether there is a vapor retarder, the condition of the deck surface, and whether the insulation is wet through or damp only at the top. That information shapes the repair or recovery plan. A roof with two layers of wet polyisocyanurate over a rusted deck is a different job than a roof with a single wet patch in a dry assembly.

Meter readings fill in the gaps between cores. Nuclear or capacitance methods can survey large areas quickly, and the readings are plotted on the grid beside the thermal anomalies. Where thermal, meter and core agree, the finding is firm. Where they disagree, we take another core.

Where cores reveal a vapor retarder or a coating on the deck, we note it, because trapped moisture behaves differently in a sealed assembly. Drying rates, the choice of replacement insulation and the venting plan all depend on what the core shows, and that is why the cuts are made at a planned set of locations instead of wherever the thermal image looks dramatic.

The Moisture Map

The map is the deliverable. It overlays the roof plan with a numbered grid, marks the wet, damp and dry areas, and indicates the cores by number. A reader can find core eleven on the grid, match it to the photograph, and read what it found. Totals by area are included, so an owner can see what percentage of the roof is affected without guessing.

We distinguish between wet and damp. Wet insulation has lost its thermal value and will keep the deck damp, which leads to corrosion in steel and rot in wood. Damp insulation may dry if the leak source is repaired and the assembly can breathe. The distinction is a judgment recorded with its basis, and it matters for cost.

The map also shows the edges of the wet areas relative to drains, penetrations and seams. When wet zones line up with a low spot, the likely cause is ponding water, and the repair plan includes drainage. When wet zones trace a line from a flashing, the source is that flashing.

We also issue a short key to the map that lists the assumptions used: the scan date, the surface condition, the meter type and the threshold for calling an area wet. A later survey can then be compared against the same key, and a change between two maps is a measured change, not an impression.

From Map to Decision

The map supports three outcomes. If the wet area is small and isolated, we cut out and replace the wet insulation, reseal the membrane and re-scan later. If the wet area is moderate and the membrane is serviceable, a section replacement may be economical. If the wet area is widespread, a full replacement is the sound choice, since insulation that is saturated cannot be recovered.

Eligibility for a recover depends on the map. Most manufacturers and building departments require the existing insulation to be dry before a new membrane goes over it, and the survey is the proof. Choosing a recover over wet insulation shifts the expense to a later failure, with a smaller budget cushion.

When insulation is replaced, the specification can improve on the original. Revisiting insulation and cover board choices during repair adds slope, thermal value and puncture resistance where the survey showed they are needed.

Why Kenosha Roofs Collect Moisture

Moisture finds its way into assemblies through small openings that repeat the same cycle. Kenosha averages about 37.6 inches of precipitation a year and 36.2 inches of snow, and temperatures range from a record low of minus 31 degrees to a record high of 105. Each freeze-thaw cycle opens seams and flashings a little, water enters, and the insulation absorbs it. Because the insulation sits between the membrane and the deck, the damage can run for years before it appears as a stain.

Racine, up the lakeshore, averages about 41 inches of snow a year. Waukegan, on the Illinois side of the lakeshore, averages 36.4 inches of snowfall a year, close to Kenosha's figure.

Where Surveys Pay Off

Surveys earn their cost where the roof is large, the assembly is thick and the consequence of hidden wetness is high. Hospital roofs and clinic roofs sit over equipment and interior spaces where trapped moisture can degrade air quality. Plants and distribution buildings protect inventory and production. Buildings under sale or refinance benefit from a survey as part of due diligence, since a buyer can price wet insulation before closing.

Owners in Zion and the surrounding towns can schedule scans alongside a visual inspection, and the findings integrate into the larger roof condition report.