Codes, exemptions & field inspections
This guide translates the available agency record into a preconstruction checklist for structural scope, minor work, and inspection release. The adopted code and the issuing official control when a field condition is disputed.
Regulatory framework
For unincorporated Franklin County, the county lists the 2021 International Building, Residential, Mechanical, Plumbing, Fire, ICC Electrical, and Swimming Pool & Spa Codes, plus the 2020 National Electrical Code. The county's on-site sewage ordinance was amended September 23, 2025 and became effective October 1, 2025; the Flood Damage Prevention Ordinance and Unified Land-Use Regulations also apply.
Inspection lane
The Building Department issues permits and inspects new construction in unincorporated Franklin County. The county publishes inspection guidelines by request; contact 636-583-6384 or building@franklinmo.gov to schedule inspections and obtain the current guidelines. Floodplain applications may require longer review and SEMA forms.
Minor-work playbook
Franklin County requires permits for construction and right-of-way use, and the county notes that municipalities and Missouri may require additional permits. The current building page publishes no broad cosmetic/minor-work exemption list; contact the Building Department to determine whether a specific repair or alteration requires a permit.
Field rule
A permit exemption generally addresses one narrow construction trigger. It does not automatically waive zoning, land-use, floodplain, shoreline, fire, energy, electrical, utility, septic, or right-of-way requirements. Obtain written confirmation when the project involves a new structure, structural alteration, change in occupancy, or concealed work.
Inspection pipeline
Request with lead time
The Building Department issues permits and inspects new construction in unincorporated Franklin County. The county publishes inspection guidelines by request; contact 636-583-6384 or building@franklinmo.gov to schedule inspections and obtain the current guidelines. Floodplain applications may require longer review and SEMA forms.
Preserve access
Do not cover framing, reinforcement, wiring, piping, damp-proofing, or life-safety work until the required inspection has been completed and documented.
Close the record
Retain the approved plans, inspection approvals, correction responses, and final certificate or occupancy release with the property file.
Contractor verification
Use the state licensing system to verify active registration, trade credentials, bond status, and liability coverage where available. Match the legal business name to the proposal and permit application.
Planning reference
A building permit is only one part of statutory compliance. Check the local zoning, ordinance, map, or land-use reference before finalizing setbacks, height, lot coverage, access, drainage, or accessory structure placement.
Open planning reference ↗Source trail
Use these direct agency or licensing links to confirm current instructions before you file, pay, or schedule work. External pages control if their information differs from this directory.
Project questions
Franklin County Building Department and Planning & Zoning Department is the identified county-level authority for this profile. Confirm that the property is in its service area before filing.
Begin with the online permit gateway listed in the application guide. If the portal does not recognize the address or project type, contact 636-583-6384 (Building Department); 636-583-6369 (Planning & Zoning).
N/A for ordinary building permits; the county publishes no fixed review timeline. Conditional-use applications must generally be submitted at least 30 days before the next Planning & Zoning Commission meeting, and staffing/workload may affect response times.
The Building Department issues permits and inspects new construction in unincorporated Franklin County. The county publishes inspection guidelines by request; contact 636-583-6384 or building@franklinmo.gov to schedule inspections and obtain the current guidelines. Floodplain applications may require longer review and SEMA forms.
For unincorporated Franklin County, the county lists the 2021 International Building, Residential, Mechanical, Plumbing, Fire, ICC Electrical, and Swimming Pool & Spa Codes, plus the 2020 National Electrical Code. The county's on-site sewage ordinance was amended September 23, 2025 and became effective October 1, 2025; the Flood Damage Prevention Ordinance and Unified Land-Use Regulations also apply. Franklin County requires permits for construction and right-of-way use, and the county notes that municipalities and Missouri may require additional permits. The current building page publishes no broad cosmetic/minor-work exemption list; contact the Building Department to determine whether a specific repair or alteration requires a permit.
Field sequencing matters
Code compliance is not only a plan-review exercise. Footings, reinforcement, framing, fireblocking, wiring, piping, insulation, weather protection, and life-safety systems each have points where the work must remain accessible. Build the inspection calendar into the trade schedule instead of treating it as a final administrative step.
When a project qualifies for a narrow minor-work exemption, keep a written explanation of why it qualifies and confirm that related zoning, utility, fire, energy, or environmental rules do not create a separate approval requirement.
Closeout file
Keep the approved plan set, inspection approvals, correction responses, contractor license verification, final certificate, and any occupancy release together. A clean record protects the owner, builder, lender, insurer, and future buyer.