Platte County, Missouri Building Permit Guide

For land outside the cities, Platte County Planning & Zoning (415 Third Street, Room 016, Platte City; 816-858-3338) issues building permits, reviews plans against the 2018 International Codes and 2017 National Electrical Code as amended, and inspects the work. Applications go through the county’s online portal, and a complete application is acted on within five working days. A new house of more than 1,400 sq ft costs $300 for the first 500 sq ft plus $0.35 for each additional square foot. Inside Kansas City, Parkville, Platte City, Riverside and the other towns, the town permits instead.

Platte County building department: who handles permitting

Platte County Planning & Zoning, led by Director Daniel Erickson, combines the county’s zoning office, its building department and its land disturbance program in Room 016 of the Administration Building, 415 Third Street, Platte City (816-858-3338, permits@co.platte.mo.us), open Monday to Friday 8:00 a.m. to 5:00 p.m. The building department issues permits for new buildings, accessory structures, additions and renovations, decks, pools, solar panels, electrical and generator work, mechanical change-outs and demolition, checks plans against the adopted codes and inspects each stage.

The county permits only unincorporated land. Each of the 19 incorporated places in the county decides its own permits; populations below are Census Bureau Vintage 2025 estimates.

Codes and what needs a county permit

Anyone who builds, enlarges, alters, repairs, moves, demolishes or changes the occupancy of a building, or installs or changes electrical, gas, mechanical or plumbing systems covered by the code, needs a county permit first. Ordinary repairs do not.

Platte County building permit fees

For example, a 2,000 sq ft house is $300 for the first 500 sq ft plus $525 for the other 1,500 sq ft at $0.35, a total of $825. The two dwelling bands do not join up, so a house just over 1,400 sq ft costs noticeably more than one just under. For commercial work the county’s permit packet asks for a $500 deposit when plans are submitted, to cover review by the county’s consulting engineering firm; any excess is billed and must be paid before the rough-in inspection. Work started without a permit pays double.

What to upload for a new house

Commercial projects add a use and occupancy statement, a site plan approved by the Platte County Planning Commission, sealed floor plans and, where it applies, approval from the Southern Platte County Fire Protection District, which also signs off solar installations inside its district.

How to apply in unincorporated Platte County

Permits for new homes and commercial buildings expire two years after issue, with one extension of up to six months; other permits, such as additions, remodels, pools, accessory buildings and solar, expire sooner. Work must start within 180 days and may not stop for more than 180 days.

County inspections

Inspectors run an AM route between 9:00 a.m. and 12:00 p.m. and a PM route between 2:00 and 4:30 p.m.; no exact time is given. The approved plans must be on site for every inspection. The stages are footing or pier, pool bonding, prebackfill (drain tile and waterproofing), ground rough once the ground plumbing and erosion control are in place, an all-trades rough-in after framing, fire blocking, electrical, plumbing and mechanical work, a gas pressure test at 20 psi minimum, and the final before anyone moves in. A suspended slab must be inspected by a Missouri-licensed engineer, whose report goes to the county.

Septic and floodplain in Platte County

Septic systems: before an on-site wastewater system is installed in unincorporated Platte County the owner needs a permit from the Platte County Health Department, which also issues permit exemptions and inspects new and repaired systems. Apply online, or mail the signed application, soil morphology report, site layout and fee to 7925 NW 110th Street, Kansas City, MO 64153 (816-858-2412).

Floodplain: FEMA’s Community Status Book lists Platte County in the National Flood Insurance Program and in the Community Rating System at class 6, worth a 20% flood insurance discount. Farley has adopted the county’s flood map panel. Camden Point, Ridgely and Weatherby Lake are in FEMA’s list of communities not participating.

Missouri building code

Missouri has no mandatory statewide building code for private construction: a county, fire protection district or municipality may adopt one (usually by reference under RSMo 67.280), and in parts of the state none has. Building codes in Missouri

Platte County permit FAQs

How much is a building permit for a new house in Platte County?

For a house of 1,401 sq ft or more, $300 for the first 500 sq ft plus $0.35 per additional square foot; a 2,000 sq ft house is $825. Smaller houses start at $200 plus $0.25 per square foot over 500.

Which building code does Platte County use?

The 2018 International Building, Residential, Plumbing, Mechanical, Fuel Gas, Energy Conservation and Swimming Pool and Spa Codes and the 2017 National Electrical Code, each as amended by the county.

How long does a county permit take?

The county acts on an application within five working days after it has all the required information.

How do I schedule a county inspection?

Through the online portal, by email to inspection@co.platte.mo.us or by phone at 816-858-3338, at least 24 hours ahead.

Does the county issue permits in Parkville or Platte City?

No. Each city issues its own permits: Parkville’s Community Development Department (816-741-9313) and Platte City’s building department (816-858-3617).

Who issues septic permits in Platte County?

The Platte County Health Department, for systems in unincorporated Platte County (816-858-2412).

Platte County permit search and official resources

• Platte County Planning & Zoning and building permits
• Platte County building permit packet
• Platte County Health Department sewage program
• Missouri DHSS onsite wastewater permitting authority by county
• City of Parkville Community Development
• Platte City building, zoning, planning and codes
• City of Riverside building inspections
• City of Weston building permit application (September 2026)
• City of Northmoor licenses and permits
• Village of Ferrelview applications and permits
• City of Weatherby Lake municipal code (Chapter 500, building codes)
• City of Lake Waukomis municipal code (Chapter 500, building regulations)
• FEMA Community Status Book, Missouri

Simplify Platte County permitting with Alliance Permitting

Alliance Permitting is a permit documentation and submission company in Missouri. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.

This guide is provided by Alliance Permitting for general information about Platte County permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.