Barndominium Builders in Madison County, Idaho
Madison County is farm country around Rexburg, and most barndominium buyers here are after a house and a working shop on open ground rather than a city lot. Out in the county the rules come from the courthouse: the Madison County Building Department issues the building permit and inspects the job, the Planning & Zoning Department applies the Unified Development Code, and Eastern Idaho Public Health signs off the septic system. The zone decides a lot. In the Agricultural zone the county puts farming first, asks for a wide lot and sets no general height limit, which suits a tall equipment bay; the Agriculture/Recreation and Rural Residential zones read differently, so check the zoning map before you make an offer. A pole barn home is the natural fit on farm ground, with posts set deep and a clear span for machinery. Barndominium kits suit owners with a crew of their own, and a turnkey build covers everything from the pad to the final inspection. If you would rather be close to town, the Rexburg page covers the city and its edge. Send us the parcel number through the survey and we will pull the zone, the setbacks and the septic questions before any design work.
Madison County at a glance
- County
- Madison County
- Building permit
- County building department
- Land use
- County agricultural and rural zoning
- Wastewater
- Septic permit: Public Health District
Barndominium Kits and Plans for Madison County
The parcel decides the budget more than the floor area does, so each option is priced against your land rather than a rate card.
Barndominium Kits
Barndominium kits for sale in Idaho: steel and pole barn shell kits sized to the snow load your building department sets, with honest help on kit prices.
Custom Plans
Custom barndominium plans for Idaho land, drawn around your site, snow load and zoning, and the Idaho residential code your building department enforces.
Pole Barn Homes near Madison County
A pole barn home sets its frame on posts and trusses (the engineering term is post-frame), which often suits a simple, wide layout with a shop bay under the same roof. Whether it fits your parcel comes down to the zoning and the site, set out below.
Metal Building Homes and Shop Houses in Madison County
A steel frame, or a shop with living quarters under the same roof: choose the structure first, then check it against the zoning below.
Metal Homes
Metal building homes in Idaho, finished as real houses: insulated for long winters, detailed against condensation, and clad for wildfire country.
Shouses
Shop houses in Idaho: a heated working shop and a home under one roof, planned around your zoning, snow load and the residential code.
Steel Construction
Steel and metal building construction in Idaho: red-iron frames and steel building kits for barndominiums, sized to your site's snow load.
Permits, Zoning and Septic in Madison County
The building permit, the zoning and the septic permit can come from three different offices. Here is who decides each part in Madison County, taken from the office or document that publishes it. Rules change, so check them again against your parcel before anything is drawn.
Madison County Building Department
The county Building Department has issued permits since 1976: its Building Inspector reviews construction drawings and inspects on site, and residential permits are applied for through an online portal. Mechanical, electrical and plumbing permits for county jobs are handled through the City of Rexburg building department. Rexburg permits inside its own limits, so ask any city first about land within its boundary.
Source: Madison County Building Department, Madison County (madisoncountyid.gov)
Madison County Planning & Zoning Department
The Unified Development Code divides the county into zones including Agricultural (AG), Agriculture/Recreation (A/R), Residential (R), Town Site (TS), Transitional Agricultural (TAG) and, since November 2024, Rural Residential 1.5. The AG zone exists to protect farming: other uses are secondary, lots must be at least 250 feet wide, and buildings sit 50 feet back from the street right-of-way.
Source: Madison County Code, Madison County (madison.municipalcodeonline.com)
Eastern Idaho Public Health
Madison County is served by Eastern Idaho Public Health, which reviews wastewater applications, does the onsite evaluation, issues the permit and inspects the installed system. No septic system may be built or modified in Idaho without a valid installation permit.
Source: Septic, Eastern Idaho Public Health (eiph.id.gov)
- No general height limit in the Agricultural zone
- The county code states there shall be no height restrictions in the Agricultural (AG) zone except those imposed by state or federal rules, with separate limits for wind turbines and towers. Side yards are 10 feet and rear yards 25 feet (Madison County Code, section 117-52, read 27 Sep 2026).
- Trade permits run through Rexburg
- The county Building Department page notes that mechanical, electrical and plumbing permits and inspections for county projects are handled through the City of Rexburg building department and are no longer issued by the State of Idaho (read 27 Sep 2026).
Source: Madison County Code, Madison County (madison.municipalcodeonline.com)
Source: Madison County Building Department, Madison County (madisoncountyid.gov)
Building on land near Madison County
Rural Madison County is mostly irrigated farm ground and river bottom, and the first check on any parcel is its zone on the county map, then whether it touches the floodplain overlay the code sets out. Irrigation ditches and laterals cross many fields; each carries a right-of-way you cannot build, fence or landscape in without the ditch owner's written permission. Without city water you will need a well, which takes an IDWR drilling permit and a licensed driller, and without sewer the septic site evaluation should come before the house is sited. Established farms keep their right to operate under Idaho's right-to-farm law, so expect dust, noise and early-morning equipment next door.
Other places in this part of Idaho
Idaho Falls & Eastern Idaho
- Idaho Falls
- Ammon
- Rexburg
- Rigby
- Bonneville County
- Madison County
- Jefferson County
- Teton County
Have land in or near Madison County? Tell us about the parcel and what you want on it, and we will check it against the local rules before anything is drawn.
Building in Madison County: questions
Start the surveyHow much does it cost to build a barndominium in Madison County?
Do I need a building permit for a barndominium in Madison County?
Which zones in Madison County allow a barndominium on acreage?
Can I build the shop before the house?
Keep reading
What usually comes next once you know what Madison County allows.
Barndominium Cost Guide
Sourced per-square-foot ranges by tier and size, and what moves the number on your land.
Read itIs a Barndominium Legal in Idaho?
Zoning, septic and who issues the permit, before you buy the land.
Read itHow Long Does It Take?
From parcel to move-in, and which steps set the clock.
Read itSources for this page
The published pages behind the Madison County facts above. Rules change, so check the current version with the office before you rely on it.
- Madison County Building Department, Madison CountyBuilding permit authority; Trade permits run through Rexburgmadisoncountyid.gov
- Madison County Code, Madison CountyLand use and zoning; No general height limit in the Agricultural zonemadison.municipalcodeonline.com
- Septic, Eastern Idaho Public HealthSewer or septiceiph.id.gov
Other places near Madison County
Nearby places with their own pages. Across a city limit or a county line the permit office, the zoning and the septic rules can change, so each is covered separately.
Building in Madison County?
Start with the survey. Tell us where the land is and what you want on it, and we will come back with which offices decide it, what the zoning allows, and a plan to fit.