Madison, St. Clair & Monroe counties · Illinois
Metal buildings in the St. Louis metro, Illinois side.
We supply shops, garages, farm buildings, commercial buildings and more across the Illinois side of the St. Louis metro. Our work reaches from Alton and Edwardsville to Belleville and Waterloo, and anywhere else you’re building. Every city and county here sets its own rules, and they change the moment you cross the river from Missouri.
Madison County code
2012 IBC
St. Clair County
Recorded affidavit
O’Fallon & Alton
2021 codes
Farm buildings
Often exempt
Each city permits inside its limits, and each county permits its unincorporated ground. For the Missouri side, see St. Louis.
What people build on the Illinois side
River towns and suburbs line the bluffs. Behind them, Madison, St. Clair and Monroe counties are grain ground and acreage.
Garages in town
Height caps and permit deadlines vary from town to town. We check the city’s rules before sizing the building.
Acreage shops
Tubular steel is usually the answer for an unfinished shop under sixty feet wide.
Machine sheds
Equipment storage goes up across the farm ground east of the bluffs. Red iron takes over past eighty feet or for combine doors.
Finished space
Steel truss is the fit here. Drywall attaches to the frame, so there’s no second wall to build.
Permitted commercial work often suits cold-formed steel, with a finished eave standard. See what a steel building costs.
Permitting metal buildings on the Illinois side of the St. Louis metro
Illinois leaves building codes to its cities and counties, so neighboring towns can be on editions years apart.
Unincorporated Madison County
- The county is on the 2012 IBC and IRC.
- Building permits are applied for in person at the Building & Zoning counter.
- Planning & Development is at 157 N. Main St, Suite 254, Edwardsville. Call (618) 296-4468.
Unincorporated St. Clair County
- Since March 1, 2025, every detached accessory building needs interior plans and a recorded Zoning Office affidavit before the permit is issued.
- A county permit is good for 12 months.
- Building & Zoning is at 10 Public Square in Belleville.
Inside the cities
- Edwardsville permits every garage and shed and caps them at 15 feet.
- Alton voids a permit if work doesn’t start within three months.
- O’Fallon moved to the 2021 codes in January 2026.
A few miles can change the code by nine years. Unincorporated Madison County builds to the 2012 codes, while Alton and O’Fallon are on 2021. The edition sets the wind and snow loads a building is engineered for, so we confirm which one governs your address before drawings are produced.
Local guides for the Illinois side
Building somewhere that isn’t listed? Tell us the address and we’ll confirm who permits it and what applies. See all of Illinois or our whole service area.
Start with a conversation
Let’s talk about your St. Louis metro project.
Tell us what you’re planning and where you’re building. We’ll help you work out the next steps.
- Tell us what and whereSend us the size, how you’ll use the building and the address.
- We check the siteWe confirm who permits the address and which code and loads apply.
- You get a clear recommendationWe recommend the frame that fits and price it against the alternatives.
Or call
314-536-8688