Building permits, zoning and land rules in Cass County, Missouri

New single-family dwellings, modular homes and single-family room additions in unincorporated Cass County require a building permit before work starts; submit the application and supporting information in person to the Building Codes Department¹. Pleasant Hill issues its own residential building permits¹¹. Lee's Summit, a city that reaches into Cass County, issues its own building permits; its code directs private sewage-system permits to Jackson County Public Works when public sewer is unavailable^12,13. Cass County Environmental Health's wastewater authority applies to unincorporated land, so confirm the septic permitting agency separately for a city address³. The county adoption document lists the 2006 International Codes and 2005 National Electrical Code but directs applicants to verify current requirements with the Building Codes Department¹⁴.

The Cass County Building Codes, Zoning & Environmental Health Department is at 30508 S. W. Outer Road, Harrisonville, MO 64701; call 816-380-8134 during its posted weekday office hours⁴. The department says building permits are not issued at application, so submit early enough for plan review⁴. The published county process says most zoning actions take about 6 weeks through the Planning Board hearing and the following County Commission hearing, while some applications need additional hearings². The residential application packet lists $350 total: $300 for the septic permit and $50 for the building application, with an additional service fee for card payments¹. The published fee schedule separately lists a $135 minimum permit fee and a $338 certificate-of-occupancy fee; ask the department which charges apply to the project¹⁴.

County zoning applies outside recognized municipalities in Cass County². Pleasant Hill sets its own zoning, as do Kansas City and Lee's Summit, cities that reach into Cass County^15,16,17. City zoning does not establish septic authority; Cass County Environmental Health administers covered wastewater systems on unincorporated land³. Single-family residences there need 1,000 square feet of living space, excluding basements, porches and garages⁷. The county's manufactured-home application applies the same 1,000-square-foot minimum to new homes and home installations, and a new manufactured home must be 1976 or newer and bear a United States Government Manufactured Home Seal⁸. District parcel sizes include more than 20 acres in A, 3 acres in R-R, 1 acre in R-S, and lots down to 1/4 acre in R-1 with public sewers; confirm the full requirements for the parcel¹⁰. Building setbacks vary by parcel: the norm is 50 feet from the front or rear property line, down to 25 feet on some parcels, and side setbacks run from a maximum of 25 feet down to 6 feet in a few older, small-lot subdivisions². Lots fronting on two streets need a 50-foot setback on each of those sides, and existing and new R-1 subdivisions have different requirements, so ask the department for a site-specific zoning determination². Newly created lots need direct, owned access to a public road rather than an easement, a 4:1 length-to-width ratio and at least 100 feet of frontage width at the building line¹⁰. Parcel divisions of any size require a survey; divisions below 20 acres intended for immediate sale and use involve additional review².

Cass County Environmental Health permits onsite wastewater systems in unincorporated Cass County³. A permit is required before construction, modification or repair of an on-site sewage disposal system for a covered system in unincorporated Cass County, and the county lists a $300 fee for a new residential system⁵. The department inspects the septic tank and absorption field before any of the system is covered, with at least 24 hours' notice⁵. Missouri separately requires a construction permit before installing or repairing most onsite systems, including residential systems on lots under 3 acres¹⁸. USDA soil data rates 0% of Cass County's mapped soils as free from severe limitations for a conventional drain field, so schedule the soil and site evaluation early rather than assuming a standard system will work⁹. For a purchase, Missouri says local agencies generally no longer inspect existing systems for transfers; a private licensed inspector can evaluate the system¹⁹.

We could not confirm whether RV occupancy or temporary camping is allowed on private land in unincorporated Cass County; ask the Building Codes, Zoning & Environmental Health Department about the proposed use and parcel district^2,4. A single-family tiny home in unincorporated Cass County must meet the 1,000-square-foot living-space minimum, and basements, porches and garages do not count toward that area⁷. The county permits that residential space to be within a manufactured building, which must be 1976 or newer⁸, but meeting the size threshold does not settle a specific tiny-home occupancy proposal⁷. New single-family dwellings require building permits, and covered onsite wastewater systems require county septic permits before construction^1,5.

1. Confirm that the parcel is in unincorporated Cass County and obtain its zoning designation from the county department^2,4.
2. Resolve septic feasibility and apply through Cass County Environmental Health before locking the house and site plan^5,9.
3. Submit the building application and plans early because the county does not issue permits when applications are filed⁴.
4. Confirm current fees with the department; the published schedule varies by project type, valuation, size and inspection circumstances¹⁴.
5. Start work and request an inspection within 180 days of permit issuance, then keep work moving because suspension or abandonment for 180 days can void the permit¹⁴.
6. Ask Road & Bridge about a drive culvert or entrance, or obtain a MoDOT permit if work enters state right-of-way^4,20.

Before buying a newly divided lot in unincorporated Cass County, verify direct, owned access to a public road: the county does not accept easements for newly created lots¹⁰. Cass County regulates development affected by floodplain and stream-buffer areas, and reconstruction or repair in a Special Flood Hazard Area after a flood event requires a building permit². The terrain is broadly gentle, with 99.4% of land at a slope of 15% or less, but 0% of mapped soils rate without severe limits for a conventional septic drain field⁹. Cass County is about 19 straight-line miles from the nearest city of 100,000 or more people and has about 160.4 residents per square mile⁹. Typical farmland value is about $4,459 per acre, while the median property-tax bill is about $2,364 per year⁹.