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

Unincorporated Ray County requires a building permit for residential construction and non-agricultural garages or outbuildings of at least 120 square feet¹. The published residential building-permit fee is $0.40 per square foot of livable space, including finished basement, bonus-room and attic space; the non-agricultural garage or outbuilding fee is $150¹. An agricultural-use-only building has a $0 permit fee and a $60 final-inspection fee, which does not establish a blanket exemption from county requirements¹. Ray County references adopted building codes, but we could not confirm the edition; ask the Building Inspector⁸. Obtain the building permit before construction: Ray County may assess a penalty from $250 to $1,000 for starting first¹.

For unincorporated land, contact the Ray County Building Inspector at 816-885-1947, Ray County Courthouse, 100 West Main St, Ste 16, Richmond, MO 64085². Planning & Zoning answers at 816-776-5398 and is available by appointment only². An owner, contract purchaser or authorized agent may file a development application, but that does not establish permission to perform every regulated trade; ask the Building Inspector about owner-builder work².

Richmond and Wood Heights issue their own building permits^9,10. Septic in incorporated Wood Heights goes through Ray County Health Department; the county Planning & Zoning septic process described here serves unincorporated land^1,4. Excelsior Springs and Lawson, cities mainly in Clay County that reach into Ray County, also issue their own building permits^11,12. Excelsior Springs requires city and county-health sewage approvals; Lawson requires the City Superintendent’s written private-sewage permit and inspection, with health requirements also applying^5,6.

Ray County Planning & Zoning administers zoning for county-regulated land, with use permissions varying by district^2,7. Richmond and Wood Heights set their own zoning; so do Excelsior Springs and Lawson, which extend into Ray County from Clay County^3,13,14,15. Those city boundaries do not transfer septic entirely to city zoning offices: Wood Heights uses Ray County Health Department, Excelsior Springs requires county-health approval alongside city approval, and Lawson has city and health requirements^4,5,6.

For unincorporated residential parcels, Ray County lists a 3-acre minimum and R-1A, R-1 and R-A acreage classes¹. Lots under 19 acres require 1,000 square feet of livable space for single-story homes; the source prints “> 1,400” for other homes, so confirm that threshold before designing¹. Animal production and accessory farm-animal raising require at least 19 acres; animal-housing buildings need 100-foot front and 50-foot side and rear setbacks⁷. These animal-building setbacks do not answer a house’s setback requirements; ask Planning & Zoning for the parcel’s residential setbacks².

New on-site septic systems in unincorporated Ray County require a county permit and a soil morphology test before application¹. Call the Ray County Septic Inspector at 816-776-5413 ext 2 for the On-Site Septic Application². Ray County publishes a $300 septic-permit fee plus $100 for self-install consultation; pay the soil evaluator separately, and use a Missouri-certified installer when hiring the work¹. The county fee sheet was updated in 2023, while Missouri suspended statewide program application fees effective August 28, 2026; ask the Septic Inspector which county charges currently apply^1,16.

Only about 4.3% of Ray County soils are rated “not limited” for conventional septic drain fields; a low share calls for site evaluation and potentially an engineered system, rather than ruling out septic¹⁷. For an existing system in a property sale, Missouri says buyers can use a private licensed inspector because local health agencies generally no longer perform transfer inspections¹⁸.

Unincorporated Ray County prohibits using an RV or accessory building as a dwelling, even during construction of a principal home, unless a hardship permit is approved². County-regulated campground rentals are a separate use and are limited to 30 days¹⁹. We could not confirm a distinct tiny-home occupancy rule; ask Planning & Zoning to classify the structure before ordering it. A tiny home proposed as a dwelling on a lot under 19 acres faces Ray County’s livable-space standards¹. A single-wide manufactured home requires at least 19 acres and a Conditional Use Permit¹.

Never-rented ADUs are permitted in R-A, R-1 and R-1A and may be allowed elsewhere through a Conditional Use Permit, but cannot have separate utilities or an address, and cannot contain ranges, stovetops, burners or hot plates²⁰. Ray County also states only one residential structure is allowed per parcel; ask Planning & Zoning how that limit applies to a proposed detached ADU^1,20.

1. Ask Ray County Planning & Zoning to confirm the district, residential use and house setbacks^1,7.
2. For an unplatted parcel under 40 acres, hire a surveyor to prepare a plat for board approval; submit meeting paperwork during the first week of the preceding month, attend with your surveyor or send the surveyor, and record the approved plat¹.
3. Complete the soil morphology test and obtain county septic approval before installing the new system¹.
4. Obtain the building permit before starting construction; the county accepts exact cash or check¹.
5. Arrange footing inspection after forms and rebar are set but before concrete; rough-in inspection covers plumbing, electrical, hard-wired smoke detectors and HVAC before insulation and sheetrock; final inspection checks safety items¹.
6. Obtain the county driveway permit if the new parcel lacks a driveway, plus MoDOT entrance permission for highway frontage¹.
7. Ask Planning & Zoning about floodplain approval: Missouri requires a permit for all floodplain development, and a regulatory-floodway project needs an engineering No-Rise Certificate^2,21.

Acreage alone does not establish a buildable residential parcel in unincorporated Ray County: the minimum lot size is 3 acres, and unplatted parcels under 40 acres require platting¹. Lots of 3–4 acres on interior subdivision streets need 200 feet of width at the building line; other lots need 300 feet¹. The plat filing fee is $175 plus $20 per lot¹. A new parcel without a driveway requires a $150 non-refundable county driveway permit, and highway frontage also requires MoDOT entrance approval¹.

Only about 4.3% of Ray County soils rate “not limited” for conventional drain fields, so evaluate the septic site before closing¹⁷. Ray County’s effective property-tax rate is about 0.8%, with a median annual bill of about $1,533¹⁷. Missouri regulates well and pump installers but allows landowners to install their own well or pump without those permits; ask Missouri DNR about construction standards and Planning & Zoning about any additional parcel requirements²².