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

Usually not for a conventional small home in unincorporated Park County. Montana exempts private residential buildings with fewer than 5 units unless they serve transient guests, and Park County is not listed as a certified local building-code jurisdiction^1,7. Farm and ranch buildings, qualifying private garages and qualifying private storage buildings also fall within state exemptions¹.

Covered commercial, larger multifamily, transient-lodging, alteration, addition or repair work can still require a state permit¹. Separate electrical, plumbing or mechanical permits may also be required¹. Park County zoning, septic, subdivision and floodplain requirements remain separate from the building-permit question^4,8,9,10.

Park County is not listed as a certified building-code jurisdiction, and the City of Livingston's certified program is limited to city limits, so the county itself does not run building-code review for rural parcels⁷. Park County Planning is the first call for zoning, subdivisions, floodplains, rural improvement districts and buildings for lease or rent⁸. Septic permits are a separate office: Park County Environmental Health issues them, and the county septic permit covers the sewage system only, not building or zoning compliance^9,11.

For work subject to the state building code, Montana's Building Codes Program handles building permits and inspections outside certified local jurisdictions¹². Applicants submit plans and an application; the state calculates fees, reviews the plans and issues the permit after deficiencies are resolved and required fees are paid¹³. The state plan-review fee is 35 percent of the building permit fee, and both fees are due before issuance¹³. Inspection applies to projects requiring a state permit, not automatically to permit-exempt homes¹.

Park County zoning is district-specific, not a blanket rule covering every parcel. The county publishes regulations for 7 mapped districts, and their limits differ². Ask Planning to identify the parcel's district before relying on a seller's description⁸.

The differences can be substantial. In the Rural Recreational Commercial district of the Cooke City/Silver Gate/Colter Pass area, the cited rule allows 1 single-family residence per 20 acres¹⁴. That district also allows an accessory dwelling unit no larger than 1,000 square feet, while temporary living quarters require an approved septic permit and are limited to the stated building season¹⁴. Certain residential districts there cap building coverage at 50 percent of lot area¹⁴. These are district examples, not countywide standards; countywide setbacks, height and minimum dwelling size remain unconfirmed, so take the parcel and proposed use to Planning^2,8.

Park County Environmental Health issues septic permits locally and publishes county septic regulations, fees, a permit application and online septic-permit access⁹. Constructing, altering or repairing an individual sewage treatment system in Park County without a valid permit from the Health Officer is unlawful³. No permit issues until the site data is reviewed and all fees are paid³. A Certificate of Subdivision Approval does not replace the drainfield permit¹⁵. Any property with human occupancy must have toilet facilities approved by Environmental Health³. Montana DEQ separately handles sanitation review for covered subdivisions¹⁵.

A homeowner installing a system for his or her own residence on his or her own property does not need an installer's license, but must pass an examination first, and Environmental Health must inspect and approve the installation before backfilling¹¹. Only 6.1% of Park County soils rate without severe limitations for a conventional septic drain field, so check septic feasibility before choosing a house site or purchase price⁶. Environmental Health's phone is (406) 222-4100⁹.

We could not confirm a countywide rule for living in an RV, occupying a tiny home, temporarily camping on private land or placing a manufactured home in Park County. Because the county publishes separate rules for 7 mapped zoning districts, ask Planning to check the parcel and proposed use rather than assuming rural land is unrestricted^2,8.

A proposal creating 2 or more spaces for RVs or mobile homes is a subdivision and requires Park County Commission review and approval¹⁰. In the Cooke City/Silver Gate/Colter Pass Rural Recreational Commercial district, temporary living quarters are allowed only with an approved septic permit from May 1 through October 15, but that narrow rule does not answer occupancy elsewhere¹⁴. Montana exempts an owner working on the owner's property from contractor registration, subject to its prompt-resale limitation; that exemption does not waive building or trade permits⁵.

1. Ask Park County Planning to identify the zoning district, subdivision restrictions and possible floodplain issues affecting the parcel^2,8.
2. Have Park County Environmental Health determine the septic path before fixing the house location; even a lot with subdivision sanitation approval still needs its drainfield permit, and no permit issues until the site data is reviewed and fees are paid^3,9,15.
3. For a qualifying small well, submit the required groundwater notice before use and complete the required filings; larger withdrawals need a water-use permit¹⁶.
4. Confirm whether the project fits Montana's exemption for a private residential building with fewer than 5 units that does not serve transient guests¹.
5. For covered work, submit plans and the state application, resolve review comments, pay the fees and arrange required inspections¹.
6. If access meets a state highway, obtain the required approach permit or right-of-way agreement from MDT¹⁷.

Start with septic feasibility: only 6.1% of county soils rate without severe limitations for a conventional drain field⁶. Next, have Planning identify zoning and floodplain constraints because district rules vary and designated floodplain development requires a permit^4,18. The published county floodplain permit fee is $450 for agricultural and fencing projects and $600 for all other projects¹⁹. Work in or near streams can require other permits before the county floodplain application²⁰.

Access also matters: a new or modified approach to a state highway requires an MDT approach permit or right-of-way agreement, while a countywide local-road driveway rule could not be confirmed¹⁷. Park County is sparsely settled at about 6.4 people per square mile, and 54.4% of its land is wooded while 54% is federally owned⁶. The effective property-tax rate is about 0.6%, with a median annual bill near $2,454⁶.