Southeast Boise
Mid-century neighborhoods near BSU and the Greenbelt with strong tenant demand from students and hospital staff. Lot sizes and zoning support the full pre-approved plan range.
Capital City · Ada County
Boise's trusted ADU builder
Fixed-price builds on the City of Boise's pre-approved plan set. Faster permits, predictable timelines, and a finished accessory dwelling unit ready for family or rent.
ADUs in Boise
Why Boise homeowners are building backyard homes
Boise is the most ADU-friendly city in Idaho, and it isn't close. The City of Boise built the pre-approved ADU plan program from scratch in partnership with local architects, sized the plans around typical Boise lots, and pre-vetted them through Planning, Zoning, and Building. When you build one of those plans on a conforming lot, you skip the design review queue and move straight to permit issuance. That's weeks of calendar time most homeowners don't realize they're paying for on a custom set.
We build the full pre-approved set in Boise: studios, one-bedrooms, two-bedrooms, and the garage-pair plans for homeowners who need parking and a unit on the same footprint. Every quote we hand you is fixed price on the plan, the site work, and the finishes. If your North End lot has an old sewer line that needs replacing or your Boise Bench property slopes harder than the topo suggests, we tell you up front before you sign anything. The number you see is the number you pay.
The rental math in Boise still works, even after the last few years of cooling. Boise State students, St. Luke's and Saint Al's staff, and the Micron expansion workforce keep one-bedroom rents in the $1,500 to $1,800 range. Foothills views, Greenbelt access, and the mature tree canopy in older neighborhoods make a well-built backyard ADU rent quickly and hold its value. Most of our Boise clients see the unit pay its own mortgage inside the first year of leasing.
- 240k
- Boise residents
- $1,500-1,800
- Typical 1-bed rent
- 16-20 weeks
- Build time
- 4.9 ★
- Client rating
Neighborhoods
Where we build in Boise
We've worked across most of Boise — here are the neighborhoods most homeowners are asking us about.
North End
Deep, narrow lots behind century-old bungalows. The 280 and 396 sq ft footprints fit the typical 50-foot frontage without crowding the rear setback or the mature tree canopy.
Read the North End ADU pageHyde Park
Walkable historic sub-section of the North End with the 13th Street commercial corridor. Same Historic District design review as the North End plus the HC-O overlay along 13th.
Read the Hyde Park ADU pageBoise Bench
Flat, rectangular 7,000 to 9,000 sq ft lots from the post-war era. Easy access for crane and concrete trucks, and most lots already have alley access for a separate ADU entrance.
Read the Boise Bench ADU pageEast End
Warm Springs Avenue and the geothermal corridor. 25×122 ft historic lots often doubled into ~6,100 sq ft parcels. NRHP-listed pockets carry historic review on a street-by-street basis.
Read the East End ADU pageBoise Foothills
Steeper sites that often need foundation engineering and grading. We pre-screen these lots before quoting and adjust the foundation scope rather than the price after the fact.
Read the Boise Foothills ADU pageNorthwest Boise
Larger lots in Collister and the State Street corridor leave room for a two-bedroom Kestrel or a garage-pair plan. HOA/CC&R review is often the binding constraint, not city code.
Read the Northwest Boise ADU pageZoning + Permits
Boise's ADU rules in plain English
Boise allows accessory dwelling units in most R-1, R-2, and R-3 zones. The City removed strict owner-occupancy rules in 2023, so a pre-approved ADU on a conforming Boise lot can be built and rented as a standalone unit. Pre-approved plans skip design review and head straight to permit.
Lot size
Minimum lot size for an ADU is typically 5,000 sq ft in most residential zones. We confirm zoning and lot dimensions on every quote before you sign.
ADU size cap
Detached accessory dwellings are capped at 900 sq ft of finished living area in most zones under the 2023 Modern Zoning Code (raised from 700). The full pre-approved plan set still sits well below the cap because the city curated conservative designs.
Setbacks
5-foot side yard and 10-foot rear yard setbacks are typical for accessory structures in R-1 zones. Corner lots and historic overlays can shift these — we verify on every site.
Parking
One additional off-street parking space is generally required per ADU. Alley access, tandem parking, and curb cuts all count when the lot supports them.
Owner-occupancy
Boise removed the owner-occupancy requirement in 2023. You can rent both the primary residence and the ADU, which opens up house-hacking and pure investment plays that weren't legal before.
Why Boise
What makes Boise a strong ADU market
Pre-approved plans built for Boise lots
The City of Boise designed this plan set for typical Boise lot widths, setbacks, and zoning. We build the plans the City wrote, not a generic template stretched to fit.
Faster permits
Pre-approved plans skip design review and go straight to building permit. That cuts weeks off a typical custom ADU timeline in Boise.
Fixed pricing, no allowances
The number on your contract is the number you pay. Site conditions get priced in before signing — no allowance line items that balloon at framing or finish.
Strong rental fundamentals
BSU, Saint Al's, St. Luke's, Micron, and the broader Treasure Valley job base keep one-bedroom rents at $1,500 to $1,800. A finished ADU rents inside the first 30 days in most neighborhoods.
Built for how Boise lives
Foothills views, Greenbelt access, mature shade — the plans work with the lot, not against it. We site every unit for light, access, and rear-yard usability.
Local crews, local accountability
Our framers, electricians, and finish carpenters work in Boise every week. If something needs a callback two years from now, we're the same phone number.
Recommended Plans
Best pre-approved plans for Boise lots
The City of Boise's pre-approved plans work in every Treasure Valley jurisdiction. Here are the picks that fit this city's lots and rental market best.
Type CThe Kingfisher
From $170k
491 sq ft · 1 · 1 ba
The 491 sq ft one-bedroom is the strongest rental performer in Boise. It rents at the top of the market to BSU staff, hospital workers, and Micron contractors, and the footprint fits cleanly on a typical Boise Bench or North End lot.
See the The Kingfisher
Type BThe Waxwing
From $135k
396 sq ft · Studio · 1 ba
The 396 sq ft Type B studio hits the sweet spot for North End and East End infill. Smaller footprint preserves rear-yard tree canopy, and the rent-per-square-foot is the highest in the plan set.
See the The Waxwing
Type G-1The Sandpiper
From $145k
396 sq ft · Studio · 1 ba
The studio-plus-garage pairs a rental unit with the parking space the City requires. It's the right answer for Northwest Boise and Southeast Boise lots where the existing house has no garage and the owner wants both problems solved at once.
See the The SandpiperBoise Lot Realities
What ADU homeowners in Boise actually check
Local specifics — not generic Treasure Valley copy.
What to check first on a Boise lot
Zoning first — Boise's R-1A, R-1B, R-1C, R-2, and R-3 residential zones all permit ADUs on lots over 5,000 sq ft, but the exact rules differ by zone. Pull your parcel from the Ada County Assessor for dimensions and easements. North End and Hyde Park lots have a historic overlay layer. Foothills lots trigger hillside review.
Common Boise lot types
Three common Boise lot shapes: (1) 50' × 120' grid lots in the Bench, Vista, and Collister — easy detached fit; (2) deeper, narrower lots in the North End with alley access — perfect for garage conversions or alley-loaded detached ADUs; (3) larger 70'+ wide lots in the East End and West Boise subdivisions — accommodate the larger Kestrel and custom plans without trouble.
Detached vs garage conversion in Boise
Detached wins in Boise when the lot is wide enough and you want rent ceiling (Kingfisher/Kestrel rents in established Boise neighborhoods are strong). Garage conversion wins in older Boise neighborhoods (North End, East End, Boise Bench) where alley-loaded 2-car detached garages already exist and homeowners want a fast, lower-cost ADU. We've built both at scale; the lot check tells you which is your honest best path.
Cost considerations in Boise
Boise is the cost baseline for the Treasure Valley — most line-item ranges in our cost guide apply directly. The two cost variables that move builds up: (1) older North End lots sometimes need a sewer lateral replacement at the trench, and (2) Foothills lots trigger geotechnical work and longer hillside review. Established Bench and Collister lots are typically clean builds at baseline pricing.
"We built the kingfisher in our North End backyard so my mom could move closer without losing her own front door. The fixed price held all the way through, and the City permit came back faster than our neighbors' kitchen remodel."
Rachel & Tom S.
kingfisher in North End · Boise, ID
FAQ
Boise ADU questions, answered
Is my Boise property zoned for an ADU?
Most R-1, R-2, and R-3 lots in Boise allow a detached ADU if the lot is at least 5,000 sq ft and meets setback requirements. Historic overlays and a few special districts add review steps. We pull the zoning and lot data for your specific address before you sign anything.
What does an ADU cost in Boise?
Our pre-approved plans range from $115k for the 280 sq ft goldfinch studio to $245k for the 695 sq ft kestrel two-bedroom. Those are fixed prices that include the build, finishes, and standard site work. Utility connections, foundation upgrades on sloped lots, and impact fees are scoped and priced before contract.
How long does an ADU build take in Boise?
Permit issuance on a pre-approved plan typically runs 4 to 8 weeks from submittal. Construction is 14 to 18 weeks after permit. Plan on roughly 5 to 7 months from signed contract to certificate of occupancy on a clean lot.
Can I rent the ADU out as a standalone unit?
Yes. Boise removed the owner-occupancy requirement in 2023, so both the main house and the ADU can be rented to different tenants. Short-term rental rules apply if you want to operate it as an Airbnb, so check the current STR ordinance before you commit to that path.
Do I need to add parking?
One additional off-street parking space is generally required per ADU. On most Boise lots that's a pad next to the existing driveway, a tandem space, or alley access in older neighborhoods. We confirm what counts on your specific lot before quoting.
Should I do a custom ADU instead of a pre-approved plan?
Custom is the right call when you have a constrained lot, a historic overlay that triggers extra review anyway, or a use case the plan set doesn't cover. For 90% of Boise homeowners, the pre-approved set saves 6 to 10 weeks of permit time and tens of thousands in design fees. We're happy to talk through both paths on a free site visit.
Nearby Areas
We also build in nearby cities
Zoning verified against City of Boise / Ada County code — last reviewed May 2026.
Boise, Idaho
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