Building permits, zoning and land rules in Blaine County, Montana

Private homes and apartments with 4 or fewer units in unincorporated Blaine County areas under state jurisdiction are exempt from state building permits unless they serve transient guests¹. Farm and ranch buildings and private garages or storage buildings for the owner's own use outside a commercial enterprise also qualify for state exemptions². Covered non-exempt new buildings, alterations, additions and repairs require a state building permit before construction². A state building-permit exemption does not settle local requirements, so confirm the project with the State Building Codes Bureau and ask the Clerk and Recorder about applicable county requirements¹.

The Montana State Building Codes Bureau has building-code jurisdiction in Blaine County areas outside certified local programs; a permit exemption should not be read as an absence of applicable codes^1,11. Submit construction plans and the Building Permit/Plan Review Application for covered work; the Bureau issues the building permit after review comments are resolved in writing and required fees are paid². The plan-review fee is 35 percent of the Bureau-calculated building-permit fee, and both are due before issuance¹. Inspections apply to projects requiring building, plumbing, electrical or mechanical permits, with certified local inspection programs applying where established¹². For state building-permit inspections, the permit holder must notify the inspector when work is ready and provide access².

We could not confirm whether Blaine County has adopted zoning for unincorporated land; county subdivision regulations do not establish countywide zoning^3,13. Inside Chinook, city zoning covers land within the corporate limits, while consent and approval for private sewer systems remain with the county sanitarian^4,14. Ask the Clerk and Recorder about zoning applicable to an unincorporated parcel; minimum dwelling size, minimum lot size, setbacks, lot coverage and building-height rules remain unconfirmed there³. Blaine County regulates subdivisions in its jurisdiction, with municipal review or joint approval also applying under the location conditions in the county regulations¹³.

Blaine County Environmental Health administers the Septic System Program and sanitary review of subdivisions, while Montana DEQ remains involved in qualifying subdivision sanitation approvals⁵. We could not confirm the septic-permit application and inspection sequence for every individual installation, so ask Environmental Health before choosing a house site⁵. Only 10.6% of Blaine County soils lack severe limitations for a conventional drain field¹⁰. Septic systems are prohibited in Blaine County floodplains; a building there that needs water and sewage facilities can proceed only with a community wastewater connection or sewage pumped outside the floodplain¹⁵. In Chinook, the county sanitarian must consent to a private-sewer connection¹⁴.

We could not confirm a Blaine County zoning rule answering long-term RV living or tiny-home occupancy on private land³. Ask the Clerk and Recorder about zoning approval and Environmental Health about septic requirements before relying on either use^3,5. A tiny home may fit Montana's state building-permit exemption for a residential building with 4 or fewer dwelling units that does not serve transient guests, but that exemption does not establish where the home may be occupied^1,3. Off-grid sanitation rules outside floodplain areas remain unconfirmed; in a floodplain, septic is prohibited and a building needing water and sewage must connect to a community wastewater system or pump sewage outside the floodplain¹⁵. A homeowner doing plumbing personally for a personal-use residence that is neither speculative resale nor rental property can qualify for the state plumbing-permit exemption, but plumbing must meet the Uniform Plumbing Code and be inspected before covering⁸. Montana also exempts owners working on their own property from construction-contractor registration, subject to prompt-sale restrictions; that exemption concerns registration rather than project approvals¹⁶.

1. Before a land transfer or subdivision filing, contact the Blaine County Sanitarian and Planner; a survey, County Commissioners approval or Montana DEQ approval may be required, and subdivisions creating building sites can take several months¹⁵.

1. Ask the Clerk and Recorder about zoning for an unincorporated parcel, then Environmental Health about the septic site and individual installation process^3,5.

1. Check flood status with the Contract Floodplain Administrator before building: a county floodplain permit is required, septic systems are prohibited in the floodplain, and construction in the floodway must be removed^7,15. Ask the administrator for the floodplain permit fee under the county fee schedule⁷.

1. For access, ask the Road Department about its county-road approach application; a state-highway entrance needs an MDT approach permit or right-of-way agreement^9,17.

1. Confirm the state building-permit exemption or obtain the required building permit before construction^1,2.

Start with sewage feasibility: only 10.6% of Blaine County soils lack severe limitations for a conventional drain field¹⁰. Check flood status because development in a regulated flood-hazard area needs a county floodplain permit, septic systems are prohibited there, and subdivisions in floodplains are prohibited^6,13,15. Confirm access with the Road Department for a county-road approach or MDT for a state-highway approach permit^9,17. Water planning matters in a county averaging 14.4 inches of precipitation a year and experiencing severe drought in about 16.6% of years¹⁰. The effective property-tax rate is about 1.5%, and the median annual bill is about $1,901¹⁰.