Roof replacement, repair and storm damage in all 6 jurisdictions we cover in St. Charles County, each with its own page: the local permit rule, the code edition it enforces and the building department's number. Of the county's 167,163 homes, 61% were built before 2000 — past the usual 25-year life of a roof — and the median year built is 1994.
We list a building official's name only where the jurisdiction publishes one — 2 of 6 here do. We list a permit answer only where the jurisdiction states one — 2 of 6 here do, and 1 of those clearly require a permit. Everything else is left blank on purpose.
St. Charles County, town by town
Each line is a summary of that town's own page.
Cottleville — 2,275 homes, median built 2012, 1% before 1940; code: 2021 IRC; re-roof permit: not published; no official named.
Lake St. Louis — 7,657 homes, median built 2000, 0% before 1940; code: 2021 Construction Codes; re-roof permit: not published; building official named (James Hoeltge).
O'Fallon — 36,206 homes, median built 2000, 1% before 1940; code edition not published; re-roof permit: yes; building official named (Nathan Lacey).
St. Charles — 32,305 homes, median built 1986, 7% before 1940; code: 2021 IRC; re-roof permit: no; no official named.
St. Peters — 25,557 homes, median built 1988, 1% before 1940; code: 2021 IRC; re-roof permit: not published; no official named.
Wentzville — 16,601 homes, median built 2008, 1% before 1940; code: 2015 I-Codes; re-roof permit: not published; no official named.
Homes across St. Charles County: the Census numbers
Built before 2000
61%
102,188 homes
Median year built
1994
2% built before 1940
Built 2000 or later
39%
64,975 homes
Owner-occupied
81%
75% detached houses
St. Charles County has 167,163 homes in the Census count, with a median year built of 1994. 2% were built before 1940, 25% before 1980 and 39% in 2000 or later; the single biggest decade was the 2000s, with 35,465 homes (21%). 75% of homes are single-family detached houses and 81% of occupied homes are owner-occupied; the count includes 4,200 mobile homes.
About 25 years is the usual working life of a roof, by the figure Missouri's insurance department publishes. On that yardstick, 102,188 homes across St. Charles County (61%) were built before 2000 and have outlived at least one roof, and 21,657 (13%) predate 1970. The 35,465 homes from the 2000s are where first replacements are coming up now.
Across the 6 places we cover here with their own Census figures, St. Charles has the oldest housing (7% before 1940) and Cottleville the newest (81% built in 2000 or later). O'Fallon is the largest, at 36,206 homes, and St. Charles has the highest share of renters (32%), where the roof is more often a landlord's decision.
Figures: U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates (tables B25001, B25003, B25024, B25034, B25035). Survey estimates carry margins of error, widest in the smallest places. Census table.
Hail reports in St. Charles County, 2016–2025
NOAA’s Storm Prediction Center logged 79 reports of hail 1 inch or larger in St. Charles County from 2016 through 2025, on 29 days. 26 were 1.75 inches or larger, and 18 of those reached 2 inches; the largest, 4 inches, fell on May 11, 2016. The busiest single day was May 16, 2025, with 30 reports.
Year
Reports
2016
5
2017
2
2018
0
2019
4
2020
3
2021
3
2022
1
2023
5
2024
20
2025
36
Counted within 5 miles of each town’s center, Cottleville has the most reports (40) and Wentzville the fewest (11). Each town’s own page lists its latest dates. Reports come from spotters and the public, so busier places log more of them.
Why the city matters more than the county
Missouri has no statewide residential building code: each city adopts an edition by ordinance, and in unincorporated areas the county's code applies. Across the 6 jurisdictions we cover in St. Charles County, that adds up to 3 different editions in force:
2021 IRC: Cottleville, St. Charles, St. Peters
2021 Construction Codes: Lake St. Louis
2015 I-Codes: Wentzville
O'Fallon publishes no edition we could read. Ask before work starts which one the roof will be inspected against.
The design figures are the same across the metro (115 mph ultimate design wind, 20 psf ground snow), so the local difference is the code edition and the permit route. What each figure does to a roof is in our St. Louis roofing code guide.
Common questions about roofing across St. Charles County
Do I need a permit to replace a roof in St. Charles County?
It depends on the city, not the county. Of the 6 jurisdictions we cover across St. Charles County, 1 requires one (O'Fallon); 1 exempts a like-for-like re-roof (St. Charles); the other 4 publish no answer either way. Each city page says which applies and links the building department.
Which building codes are in force across St. Charles County?
Across St. Charles County the jurisdictions we cover enforce 3 different editions: the 2021 IRC in Cottleville, St. Charles, St. Peters; the 2021 Construction Codes in Lake St. Louis; the 2015 I-Codes in Wentzville. 1 publishes no edition we could read. The edition in force is the one your roof is inspected against.
How old are the houses across St. Charles County?
The Census Bureau's 2020–2024 estimates put the median year built across St. Charles County at 1994, with 2% of its 167,163 homes built before 1940 and 39% in 2000 or later. 61% were built before 2000, so most have had at least one new roof already.
Does a roofer need a license in St. Charles County?
Missouri has no state roofing license; licensing and registration are set city by city. Among the cities we cover in St. Charles County, Wentzville, Lake St. Louis require a contractor to be licensed or registered with the city before a permit is issued.
Which St. Charles County jurisdictions name their building official?
2 of the 6 we cover publish a name: Lake St. Louis, O'Fallon. Where a name is published, it is on that city's page with the department's own number.
Town rules from each jurisdiction's own pages, researched 2026-09-09; housing, Census ACS 2020–2024; hail, NOAA Storm Prediction Center. Sources: data.census.gov · www.spc.noaa.gov · www.stlpr.org. Rules and staff change; check with the jurisdiction.
Free roof inspection
Roofing anywhere in St. Charles County
Free inspection, a written scope, and photos you keep either way.
