Illinois Roofing License IDFPR #19HC00108700 · GAF Certified Contractor
If you suspect your roof took hail damage in a recent Illinois storm, the assessment process is more standardized than people realize. Adjusters and contractors look at the same indicators in the same order. This guide walks through how a hail damage roof assessment is actually done – what witness marks are, how test squares work, the difference between cosmetic granule loss and a real claim, and what a homeowner can do (and shouldn’t do) before the adjuster shows up.
What hail does to an asphalt roof
Hail damage to asphalt shingles takes two forms:
1. Bruising (the real damage). A hailstone strike compresses the granules into the asphalt mat below and can crack the fiberglass reinforcement layer underneath. From the surface it looks like a circular dark spot (where granules were displaced) but the structural damage is the cracked mat. Bruises don’t always leak immediately – many sit for 6-18 months before water finds the crack and starts traveling under the shingle.
2. Granule loss without bruising (often cosmetic). Hail can knock granules off the surface without cracking the underlying mat. The shingle looks worse but it’s still structurally sound. This is the gray area: granule-loss-only damage shortens shingle life (UV breaks down the asphalt faster without granules protecting it) but doesn’t cause immediate leaks.
The line between “bruise that warrants a claim” and “cosmetic granule loss” is what every assessment is trying to draw.
Witness marks – confirming a hail event hit your address
Before evaluating the shingles, both contractors and adjusters look at “soft metals” on the property – items that hail dents easily and definitively. These include:
- Aluminum gutters and downspouts (dents in the smooth metal)
- Roof flashing (dents in chimney flashing, valley flashing, drip edge)
- Aluminum siding or trim
- Satellite dishes (the bowl is thin aluminum)
- Garbage cans, deck furniture, sheds
- Vehicles parked outside during the storm
The presence of witness marks on multiple soft-metal items confirms a hail event hit your property. If your gutters are pristine but you’re claiming hail damage to the roof, that’s a flag for the adjuster.
The other reference: NOAA’s Storm Prediction Center keeps a database of hail reports by location and date. If you suspect a specific storm date, we can pull the radar-derived hail size estimate and ground-spotter reports for your zip code to corroborate. This is part of every Trill Roofing storm inspection report.
The test square method
The industry-standard assessment method is the “test square”:
- The contractor or adjuster picks a 10 ft x 10 ft section of one roof slope (100 sq ft, exactly one “square” in roofing terms)
- They mark each hail bruise found within that square with chalk
- The count of bruises in the test square is recorded
- The process is repeated on each roof slope (typically 4 slopes on a simple gable: north, south, east, west, but more on complex roofs)
Each carrier has its own threshold for “functional damage” but a common one is 8 or more bruises per 100 sq ft test square on a slope where hail would have hit (windward-facing slopes typically get hit harder than leeward).
If multiple slopes meet the threshold, the typical adjuster scope is replacement of all affected slopes (often the entire roof, since you can’t realistically replace one slope without affecting the rest).
Bruise vs. cosmetic – the gray zone
Not every dark spot is a bruise. Several non-damage conditions can look similar:
- Manufacturing defect granule loss – premature granule loss that’s the manufacturer’s responsibility, not a hail claim
- Foot traffic – granule loss in walking paths used by HVAC technicians or chimney sweeps
- Algae/lichen damage – circular discoloration that mimics bruising
- Blistering – bubble-like surface defects from moisture in the shingle during manufacturing or ventilation issues
The diagnostic: a real hail bruise feels soft when you press on it. The granules are displaced and the mat below has cracked, so there’s give in the surface. Cosmetic granule loss or blistering feels firm.
Contractors trained in hail assessment learn to identify the tactile difference. So do experienced adjusters. Less experienced adjusters sometimes mis-categorize, which is one reason supplemental documentation and second opinions matter.
What a homeowner should and shouldn’t do
If you suspect hail damage:
Should:
- Walk the perimeter of the house and look at soft metals (gutters, AC unit fins, deck furniture) for impact marks
- Take photos with date stamps
- Note the suspected storm date
- Schedule a free inspection from a local contractor (not a storm chaser) – we’ll get on the roof, do test squares, and write up a report
- If the report confirms damage, file the claim with your carrier
- Request that the adjuster meet you at the property for the inspection
Shouldn’t:
- Climb on the roof yourself – too dangerous, and you can damage shingles during inspection
- Sign anything from a door-to-door contractor before having an independent inspection done
- Pay any contractor upfront before the claim is approved
- Let a contractor file your claim for you (only you or a public adjuster can do that legally in IL)
- Accept a settlement check until you’ve reviewed the scope with your contractor
Working with the adjuster
When the adjuster comes out, the best outcome happens when your contractor is on the roof at the same time. The adjuster does their test squares; the contractor does theirs. If the counts match, the scope is straightforward. If they differ, the contractor can show the adjuster the bruises they identified in real time, which usually resolves the discrepancy on the spot.
If the initial scope misses items that the IL building code requires (ice barrier at eaves, drip edge, code-compliant ventilation), we submit supplemental documentation with the line items and the code citations. Most carriers approve supplements when properly documented – it just requires the contractor to know what to ask for.
Trill Roofing handles the adjuster-meet coordination on every storm claim we work on. Schedule a free post-storm inspection at /free-inspection/ or call (618) 304-7094.
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