Detached Garage Builder in Ennis, MT
Ennis is the rare place around here that publishes explicit accessory structure standards: 3 foot side yard, 6 foot rear yard, 4 feet of separation from the house, and no taller than the main building.
No obligation. Every estimate starts with a walkthrough of the lot, the access and where the building can actually sit.
Ennis, MontanaBuilding here
What Ennis is actually like to build in
Frost depth follows the City of Bozeman published requirement, which we treat as the regional standard because the ground freezes the same depth on either side of a jurisdiction line.
Ennis is an incorporated town of 917 people on the Madison River at 4,941 feet, with the Tobacco Roots to the northwest, the Gravellys to the southwest and the Madison Range to the east. It incorporated in 1956, and it is worth knowing that Madison County planning reviews and approves applicable permits on behalf of the town.
The town has adopted zoning under Title 11, and unusually for this area it publishes accessory structure standards clearly enough to be quoted. A detached structure needs a minimum 3 foot side yard and 6 foot rear yard setback, a minimum 4 feet of separation between the detached structure and the main structure, and it may not occupy more than 50 percent of any required rear yard. In residential districts an accessory building or garage may not exceed the height of the principal structure and may not sit in a utility easement. Accessory buildings are prohibited between the front lot line and the required front building line. No structure may sit within 15 feet of the mean high water mark of a watercourse, with 5 feet of natural vegetation retained.
That height rule is the one to plan around. On a single-storey house, a garage cannot exceed the house height, which rules out a tall RV garage on many town lots.
Outside town limits, unincorporated Madison County has not adopted and does not currently enforce zoning regulations. The county administers land use through a sanitarian, a planner and a floodplain administrator, and enforces subdivision and floodplain development regulations. Madison County is also not a certified building code jurisdiction, so the state private garage exemption applies.
The ground is a terrace and alluvial fan landscape. The Cedar Creek alluvial fan and the Cameron Bench are the notable features, and the Madison Valley is an active extensional basin with a Quaternary fault zone, so seismic design should not simply be borrowed from Bozeman's published values.
Local conditions
What shapes a garage project in Ennis
Published and specific
3 foot side yard, 6 foot rear yard, 4 feet of separation from the main structure, and no more than 50 percent of any required rear yard. Rare clarity for this area.
Capped at the house
In residential districts an accessory building may not exceed the height of the principal structure. On a single-storey house that constrains a garage with a loft and rules out most RV garages.
No county zoning at all
Madison County has not adopted zoning regulations. Outside town limits, subdivision and floodplain rules apply, plus septic through the county sanitarian, and the state garage exemption.
What we build
Buildings we put up in and around Ennis
Each of these raises a different structural and permit question. The pages below cover what is involved rather than repeating the same paragraph with the building name swapped.
Detached Garages
Two, three and four-car detached garages built on their own footings, sized to the lot and the setbacks rather than to a catalogue.
What is involved →Shops & Workshops
Heated, insulated working buildings with the ceiling height, power and floor drainage that real work needs.
What is involved →RV Garages
Tall-door buildings sized around the vehicle you actually own, with the door height and approach worked out before framing.
What is involved →Garage With Loft
Storage or bonus space over the bays. A different roof, a different stair and a different structure from a single-storey build.
What is involved →Garage Apartment (ADU)
A dwelling above the garage. Different permit path, different code, and the one build here where the rules changed recently.
What is involved →Pole Barn Garages
Post-frame buildings for larger clear spans on acreage, where a stick-framed garage costs more than it needs to.
What is involved →Garage Slabs & Concrete
Footings, frost walls, slabs and aprons. The part of the build that is impossible to fix later.
What is involved →Garage Demolition & Rebuild
Taking down a failing garage and rebuilding on the same footprint, including what to do about the old slab.
What is involved →Before design
The Ennis checklist
Five things we establish on a Ennis property before drawing anything. Most of them cost nothing to check and a great deal to get wrong.
- Whether the parcel is inside town limits, where zoning applies, or in unincorporated Madison County, where it does not.
- The height of the principal structure, because in town that caps the garage height.
- Distance to the Madison River. No structure within 15 feet of the mean high water mark, with 5 feet of vegetation retained.
- Utility easements, which an accessory building may not occupy.
- Septic permitting through the Madison County sanitarian, with a county-licensed installer required.
Nothing on this page is a code determination. Codes, fee schedules and zoning change, and Bozeman replaced its entire development code effective 1 February 2026 as a reminder of how fast that happens. We verify every figure against the current regulation for your specific parcel before design, and you should confirm anything you intend to rely on with the authority that administers it.
Questions
Building a garage in Ennis
How close to the property line can a garage go in Ennis?
The town code sets a minimum 3 foot side yard and 6 foot rear yard for a detached accessory structure, with at least 4 feet of separation from the main structure. An accessory building may not take up more than 50 percent of any required rear yard, and it cannot go between the front lot line and the required front building line.
Those are the published figures. We confirm them against the current code for your lot before siting.
Can I build a tall RV garage in Ennis?
Inside town limits, probably not on a single-storey property. The code says an accessory building or garage in a residential district may not exceed the height of the principal structure.
Outside town limits in unincorporated Madison County there is no zoning at all, so height is not constrained that way. That is a genuine reason people build the taller building on the county side.
Who issues permits here?
The town has adopted zoning, and Madison County's planning department reviews and approves applicable permits on behalf of the Town of Ennis. Permits include a zone site permit, plus fence, sign, encroachment, temporary use and conditional use permits.
Madison County is not a certified building code jurisdiction, so the building code side falls to the state, which exempts a private garage for the owner's own use.
What snow load applies at Ennis?
There is no station at Ennis itself. Nearby Madison County stations bracket it: Norris at the Madison powerhouse, 4,745 feet, reads 34.9 psf, and Pony at 5,590 feet reads 44.3 psf. Ennis at 4,941 feet sits between them.
Average annual snowfall is around 115 inches. We pull a site figure by coordinates rather than interpolating from a table.
Is seismic design different here?
Worth taking seriously. The Madison Valley is an active extensional basin with a Quaternary fault zone, and the Madison Range fault moved within the last 130,000 years. Bozeman's published seismic design category should not simply be borrowed for a Madison Valley site.
For a wood-framed garage the practical effect is in bracing and connections, particularly on a wall with a large door opening in it.
Nearby
Other areas we cover
Next step
Get a range for your Ennis property
Send the address and a rough idea of the building. We come back with what the ground and the jurisdiction allow, and what it is likely to cost.