Ballwin, Missouri requires a city building permit for all kinds of construction, from additions and decks to sheds, barns and fences1. The City of Ballwin, not St. Louis County, administers its own zoning under Ordinance No. 5572. We could not confirm who handles septic permits inside city limits, so ask the St. Louis County Department of Public Health.
At a glance
- Building permit
- Required for all kinds of construction inside Ballwin1
- Zoning
- Ballwin's own zoning ordinance (Ordinance No. 557)2
- Occupancy permit
- Required before a new resident, tenant or business moves in3
- R-1 minimum lot
- 20,000 square feet4
- R-1 minimum home size
- 1,150 sq ft single-story; 850 sq ft ground floor and 1,700 sq ft total for multi-story5
- R-1 setbacks
- Front 40 ft, side 10 ft, rear 25 ft6
- Septic
- Not confirmed inside city limits; ask St. Louis County Department of Public Health7
Who to call
Building permits
City of Ballwin Building Inspections Department
Building permits and occupancy inspections inside Ballwin city limits; applications go through the city's MyGov portal
1 Government Ctr Ballwin, Missouri 63011
Septic permits
St. Louis County Department of Public Health
County onsite wastewater (septic) permitting contact; whether it applies inside Ballwin city limits is unconfirmed
6121 N Hanley Rd, Berkeley, MO 63134
Contact details are copied from each office’s official page and were checked against it on October 24, 2026.
Off-grid gear
Going off-grid in Ballwin means bringing your own water and power. The kit we’d start with:
- Water Crystal Quest Filter any source — well, rain, or creek — to drinking-clean.
- Power Bluetti Solar generators and home battery backup for living off the grid.
- Septic Soil percolation test kit Run your own perc test before paying an engineer — the first thing a septic office asks about.
- Water Well water test kit Bacteria, nitrates, hardness — know what the well on a parcel is really pumping.
These are affiliate links — we may earn a commission, at no cost to you. As an Amazon Associate, Bolthole Index earns from qualifying purchases.
Do you need a building permit in Ballwin, Missouri?
Yes. Ballwin requires building permits for all kinds of construction, including room and garage additions, basement finishes, sheds, barns, fences, decks, satellite dishes and swimming pools18. The city says to call the Building Inspections Department if you are unsure whether a particular project needs one8.
Ballwin also requires an occupancy inspection: all occupied buildings must be inspected and certified for compliance with the Ballwin Housing Code before a new resident, tenant or business can occupy them9. New occupants must obtain an occupancy permit first3. Plan for this when you buy a house inside the city.
These are the city's rules for land inside Ballwin. For land outside city limits, see the St. Louis County page.
Who issues building permits in Ballwin, and how do you apply?
The City of Ballwin issues its own building permits through its Building Inspections Department, at (636) 227-21298. The city accepts permit applications and payments online through its MyGov portal, so you do not have to come into the Government Center108.
The city currently uses the 2015 building code standards, and it has proposed an update to the 2024 International Codes11. We could not confirm a published permit fee schedule, so ask the department for the cost of your project. Unincorporated St. Louis County has its own permit office, but that office does not issue Ballwin's permits.
Does Ballwin have zoning, and what does it mean for lot size and setbacks?
Yes. Ballwin has its own zoning, set out in Ordinance No. 557 as amended2. The rules differ by district. In the R-1 Single-Family district, the minimum lot is 20,000 square feet4. Setbacks in R-1 are at least 40 feet in front, 10 feet on the sides and 25 feet in the rear, and the front setback is 60 feet next to Manchester Road or other major roads6. Buildings in R-1 may be at most 35 feet and three stories tall12.
In R-1, a single-story house must be at least 1,150 square feet, and a multi-story house needs 850 square feet on the ground floor and 1,700 square feet in total5. The city calls its chart a simplified summary, so read the full ordinance for your district before you buy13. Subdivision plats also need adequate storm sewers14.
How do septic permits work in Ballwin?
We could not confirm who administers septic permits inside Ballwin city limits, or whether a septic permit is required there. In St. Louis County generally, onsite wastewater permitting runs through county authorities, and Missouri lists both the county plumbing department and the county health department7. Missouri requires a construction permit before installing or repairing most onsite wastewater systems15.
Call the St. Louis County Department of Public Health at (314) 615-0600 before you assume a lot is on sewer or septic16. County soil data rate only about 5% of soils as not limited for a conventional drain field, so a lot without sewer service will likely need a site evaluation or an engineered system17. That figure is for St. Louis County as a whole.
Can you live in an RV or tiny home on your land in Ballwin?
We could not confirm. Ballwin's code has a chapter on trailers and recreational vehicles, but we did not find an operative rule on living in an RV, camping on private land, or occupying a tiny home. Ask the Building Inspections Department at (636) 227-2129 before you plan to live in one8. Because Ballwin has its own zoning, the county's unincorporated-area rules do not answer this question2.
Building a home in Ballwin: the steps, in order
- Confirm the zoning district and its lot, setback and height limits in Ballwin's zoning ordinance213.
- Ask the County Department of Public Health whether the lot needs a septic permit or is served by sewer16.
- Call Building Inspections at (636) 227-2129 and apply for your building permit through MyGov810.
- If you touch a state highway driveway, MoDOT requires a permit for driveways on its right-of-way18.
- Get the occupancy inspection and permit before anyone moves in3.
What stays with St. Louis County, and what to check before you buy
Septic, wells and flood questions may involve St. Louis County or the state even inside Ballwin. Missouri requires a water-well installation permit to construct or repair a well, and we could not confirm a Ballwin-specific well rule19. County flood-plain rules in the sources we reviewed apply to unincorporated areas, and we could not confirm Ballwin's own floodplain rule, so ask the city before you buy near a creek. Typical property tax in St. Louis County is an effective rate of 1.2%, with a median bill of $3,193 a year2021. For land outside city limits, use the St. Louis County page.
Watch-outs
- The city's building code is the 2015 standards today, and Ballwin has proposed moving to the 2024 International Codes, so ask Building Inspections which edition applies to your project11.
- We could not confirm an owner-builder exemption, a permit fee schedule, or driveway rules inside Ballwin, so call Building Inspections at (636) 227-21298.
- The single-family district figures come from the city's simplified summary chart, and other zoning districts have different standards13.
Sources
- Building Permits & Occupancy Inspection Information (Ballwin), quoted and re-checked
- Ballwin Code of Ordinances, Chapter 19—Planning and Development (Ballwin), quoted and re-checked
- Building Permits & Occupancy Inspection Information (Ballwin), quoted and re-checked
- Ballwin Residential Zoning Districts (Ballwin), quoted and re-checked
- Ballwin Residential Zoning Districts (Ballwin), quoted and re-checked
- Ballwin Residential Zoning Districts (Ballwin), quoted and re-checked
- OWTS Construction Permit Process — St. Louis County authorities, quoted and re-checked
- City of Ballwin Building Inspections Department (ballwin.mo.us)
- Building Permits & Occupancy Inspection Information (Ballwin), quoted and re-checked
- Building Permits & Occupancy Inspection Information (Ballwin), quoted and re-checked
- Building Permits & Occupancy Inspection Information (Ballwin), quoted and re-checked
- Ballwin Residential Zoning Districts (Ballwin), quoted and re-checked
- Ballwin Residential Zoning Districts (Ballwin), quoted and re-checked
- Ballwin Code of Ordinances, Chapter 25—Subdivisions (Ballwin), quoted and re-checked
- OWTS Construction Permit Process, quoted and re-checked
- St. Louis County Department of Public Health (stlouiscountymo.gov)
- Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
- Permits | Missouri Department of Transportation (Missouri statewide rule), quoted and re-checked
- Water Wells - PUB2945, quoted and re-checked
- Effective property tax rate: Bolthole Index county data
- Median property tax bill: Bolthole Index county data
Written October 24, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.