Territory Intelligence Brief · No. 01
The Cook County exterior market, measured.
Every number on this page comes from the official record: the county assessor's file on 1.11 million residential parcels, county roof permits, FEMA and First Street flood layers, and NOAA's storm archive. No survey, no estimate-of-an-estimate. This is the market you're bidding in.
1,114,335Residential parcels measuredCounty assessor
1954Median year built, county-wideCounty assessor
930Assessor neighborhoods scoredTerritoryX models
82,591Homes with a roof permit on fileCounty permits · 94,645 indexed
01 · Housing stock
This is an old-roof, old-wall market.
The median Cook County home was built in 1954, before the interstate system was finished. 84.6% of the county's 1.11M homes predate 1980, and nearly a third predate 1940.
For every exterior trade, that skew is the market: original and second-generation components aging out at scale, decade after decade, in dense clusters rather than scattered lots.
The read for contractors
Finding work in this county isn't the problem. Finding the blocks where the aging is furthest along, with recent replacements already netted out, is. Age alone is table stakes; age minus recent permits is a campaign.
Homes by build eraAssessor · n=1,114,319
02 · The roof market
Nine roofs in ten are asphalt shingle.
89.4% of Cook County's residential roofs are asphalt shingle on the assessor's file. That is a remarkably uniform market, one where the replacement cycle rather than the product mix decides who wins the season. Tar & gravel (mostly flat-roof stock) is a distant second at 8.2%.
Meanwhile 82,591 homes, 7.4% of the stock, carry a roof permit on file. The index holds 94,645 permits; the rest never match a residential parcel. Those are the homes a smart campaign quietly removes before the first postcard prints: they already bought.
The read for contractors
In a one-product market, targeting is the differentiator. Every re-roofed home you mail is pure waste at today's postage. Permit suppression is the cheapest ROI move in direct mail.
Roof material mixAssessor roof_material
03 · Re-roof waves
Replacement comes in waves, and the waves are on file.
Roof permits don't arrive evenly. They spike, township by township, in the seasons after severe weather and reassessment cycles, and each spike leaves two signals behind: the homes that replaced (suppress them), and the same-vintage neighbors that didn't (they're aging on the same clock).
The largest township-year permit waves in the county file are listed to the right. Worth township's 2019 wave is the biggest single cohort on the file (county-wide permit coverage completes in 2020, so earlier years are read within a township's own series), which means the Worth-area homes that didn't replace in that wave are now six-plus seasons further along than their re-roofed neighbors.
The read for contractors
A permit wave is a map of demand that already proved itself. Campaign the non-replacers inside a past wave's footprint before your competitors rediscover the same storm.
Largest township permit wavesCounty roof permits
| Township | Year | Roof permits |
|---|---|---|
| Worth | 2019 | 3,115 |
| Bremen | 2024 | 2,162 |
| Hanover | 2023 | 2,147 |
| Worth | 2020 | 2,138 |
| Evanston | 2020 | 1,895 |
| Palos | 2024 | 1,832 |
| Orland | 2025 | 1,825 |
04 · Hail history
Hail is a real, recurring Cook County event.
NOAA's storm archive records 12,000 hail reports across Illinois since 1955, and 7,262 of them (60.5%) logged hail of one inch or larger, the size class contractors treat as roof-relevant. 653 of the state's reports fall inside Cook County, with 111 in the most recent five years of the archive (2022–2026; 2026 rows preliminary).
We use the hail layer as history, not as a damage claim: it tells you which townships have been hit, when, and how often. That is the raw material for a storm-cohort read like the permit waves above.
The read for contractors
Storm chasing is a race. Storm history is a strategy: the past hail footprint plus the permit record tells you where replacement demand was created and how much of it was never absorbed.
NOAA hail archive · IllinoisNOAA SPC · 1955–2026
05 · Water & basements
The drainage market is bigger than the floodplain.
Only 11,100 Cook County homes sit in a FEMA Special Flood Hazard Area, about 1% of the stock. But 108,315 homes carry a First Street flood factor of 5 or higher, nearly ten times the mapped floodplain. Water risk in this county lives outside the official lines.
And the exposure has somewhere to go: 82.1% of Cook homes have a full or partial basement: 671,371 full, 243,960 partial. That's the structural reality behind the waterproofing, drainage, and foundation trades here.
The read for contractors
If you sell drainage or waterproofing on the FEMA map alone, you're marketing to 1% of your real market. The flood-factor layer plus basement stock is the actual demand surface.
Basement stockAssessor basement_type
06 · Walls & ownership
Almost half this county can't buy siding.
44% of Cook homes, 490,445 of them, are masonry. They will never buy vinyl siding, and every one of them in a siding mail drop is money burned. Frame (30.9%) and frame-plus-masonry (23.6%) are the real siding market, and the assessor's file says exactly which homes they are.
On the buyer side, 84.9% of Cook homes are owner-occupied, so the decision-maker usually lives at the address. The 15.1% absentee slice is its own segment: reachable, but with different economics and a different pitch.
The read for contractors
Wall material and occupancy are on the public record, home by home. The trades that filter on them stop paying to persuade homes that structurally, or economically, were never going to say yes.
Exterior wall materialAssessor ext_wall_material
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Method & sources
Figures are computed from official public records covering 1,114,335 Cook County residential parcels: the Cook County Assessor's property characteristics file (build year, roof material, wall material, basement type, ownership), county building-permit records (roof permits, township permit waves), FEMA flood zones and First Street flood factors as published in the county's open-data universe file, and the NOAA Storm Prediction Center severe-weather archive (hail reports, 1955–2023). Percentages are shares of parcels with the relevant field populated. Everything on this page is aggregate. No individual home is identified, and nothing here is a claim about any specific property's condition.
The same layers, scored home-by-home and neighborhood-by-neighborhood, are what a Territory X-Ray runs on. This brief is refreshed as the underlying county files update.
Cook County Assessor · characteristics & ownership
County permit records · roof permits
FEMA + First Street · flood layers
NOAA SPC · hail archive
This is the county-level read. Your territory has its own.
The Territory X-Ray runs these same layers on the specific towns you work: ranked neighborhoods, reason codes, and the first campaign worth your money.
Request a Territory X-Ray