4-8 weeks faster permits
Skip Boise's design review stage entirely. Pre-approved plans permit in 3-5 weeks vs 8-12 weeks for custom.
Boise · Pre-Approved · Permits Faster
Boise pre-approved ADU plans
Six City of Boise pre-approved plans, all built by a licensed local team. Skip 4–8 weeks of design review and roughly $8–15k in architecture fees. We help you pick the one that fits your lot, budget, and use case.
Build any of Boise's six pre-approved ADU plans
In 2026, the City of Boise published six pre-approved ADU plans — Goldfinch, Waxwing, Kingfisher, Kestrel, Sandpiper, and Osprey — designed to give homeowners a faster, cheaper path to a permitted accessory dwelling. Each plan has already cleared Boise's Planning, Zoning, and Building reviews. Building one of them skips the design review stage entirely, dropping the permit timeline from 8–12 weeks to 3–5 weeks and saving the $8–15k architecture fee that custom plans require.
The plans don't change construction quality, finish freedom, or homeowner choice on what the inside looks like. They simply lock the structural footprint, exterior elevations, and code-relevant details to a known-good drawing set. We build all six on Boise-area lots — pre-approved is our default path because the math almost always favors it for the homeowner.
Why pre-approved plans save time and money
$8-15k design fee savings
No architect needed. The City of Boise published these plans for free as part of the 2026 pre-approved program.
Already code-compliant
Each plan has passed Boise's Planning, Zoning, and Building review. Construction proceeds against a known-good drawing set.
Predictable cost ranges
Same square footage means the same line-item budget. Quotes get tighter; surprises get fewer.
What "pre-approved" does and doesn't mean
Pre-approved doesn't mean "your lot is approved" — it means the plan itself has been reviewed. Site-specific review still applies.
What pre-approved does mean
- Boise has reviewed and approved the design package as code-compliant
- You can build the plan as-drawn on a conforming lot
- City review skips the design stage and goes straight to permit
- Finish choices (cabinets, counters, flooring, fixtures) are fully customizable
What pre-approved does not mean
- It does not mean the city has approved your specific lot
- It does not skip site-specific plan check (utilities, setbacks, easements)
- It does not allow structural or exterior elevation changes
- It does not waive HOA review, hillside overlay, or historic-overlay rules
Compare the six pre-approved plans
Click any plan for the full detail page — specs, finish tiers, cost ranges, FAQs, and the case for picking it over its closest sibling.
Type A · 280 sqft · Studio
The Goldfinch
Smallest. Cheapest. Cap-rate king.
The smallest pre-approved Boise ADU plan — a 280 sq ft studio that fits the tightest lots and the cleanest budgets.
From $115k →
Type B · 396 sqft · Studio
The Waxwing
Real living + sleeping zones in 396 sq ft.
A 396 sq ft studio with more breathing room — full living, kitchen, and bath in a thoughtfully laid-out single space.
From $135k →
Type C · 491 sqft · 1BR
The Kingfisher
The 1-bedroom landlord favorite.
Boise's pre-approved 491 sq ft one-bedroom — separate bedroom, full kitchen, full living room, ready to permit.
From $170k →
Type D · 695 sqft · 2BR
The Kestrel
The only pre-approved 2-bedroom.
The largest pre-approved Boise plan — a 695 sq ft two-bedroom that lives like a small house.
From $245k →
Type G-1 · 396 sqft · Studio
The Sandpiper
Studio + garage, one foundation.
A 396 sq ft studio paired with a single-car garage — pre-approved, dual-purpose, builds your storage and your rental in one footprint.
From $145k →
Type G-2 · 376 sqft · Studio
The Osprey
Sandpiper for narrow side-yard lots.
Sister plan to the Sandpiper — 376 sq ft studio with garage, a different layout, same pre-approved status.
From $140k →
Which plan fits your lot?
Four factors usually decide. The lot check runs your address against each one and recommends the plans that actually fit your buildable envelope.
Buildable envelope
Your lot's buildable area after subtracting setbacks, easements, and the existing house footprint. Smaller plans (Goldfinch, Waxwing) fit lots where Kingfisher and Kestrel can't.
Existing structures
If you have an existing garage you want to keep, garage-combo plans (Sandpiper, Osprey) may not fit. If you lost your garage to a prior conversion, they're often the right call.
Use case
Cap-rate rental vs aging-parent suite vs guest house vs family ADU. Each plan has a clean primary use — pick yours first, then check fit.
Budget
Plans range from $115k (Goldfinch Essential) to $345k (Kestrel Premium). Don't stretch for a bigger plan if it forces you down to Essential finish — finish quality compounds, square footage doesn't.
Pre-approved plan cost ranges (2026)
Turnkey, fixed-price numbers. Includes site work, foundation, framing, MEP, insulation, drywall, finishes, and paint per finish tier. Excludes furniture, premium appliance upgrades, and landscaping beyond rough grade.
| Plan | Sq Ft | Beds | Essential | Standard | Premium |
|---|---|---|---|---|---|
| Goldfinch | 280 | Studio | $115k | $130k | $150k |
| Waxwing | 396 | Studio | $135k | $160k | $190k |
| Sandpiper | 396 | Studio + garage | $145k | $175k | $210k |
| Osprey | 376 | Studio + garage | $140k | $170k | $200k |
| Kingfisher | 491 | 1 BR | $170k | $200k | $235k |
| Kestrel | 695 | 2 BR | $245k | $285k | $345k |
See the full breakdown on our Boise ADU cost page or use the cost calculator for a custom range.
Permit considerations
Pre-approved plans skip design review but still go through plan check and inspections. The timeline advantage is real and predictable — the rest of the permit process is identical to a custom build.
- Pre-approved permits typically issue in 3-5 weeks from submittal
- Custom plans typically take 8-12 weeks due to design review
- City-specific overlays (Foothills, historic, hillside) add timeline regardless
- Median Boise pre-approved permit: 27 days; slowest custom we've handled: 14 weeks
- Plan check fees and impact fees apply on both paths — pre-approved doesn't waive city fees
Full timeline: Boise ADU permit process guide.
Pre-approved plan FAQs
What are Boise's pre-approved ADU plans?
The City of Boise published six ADU plans in 2026 — Goldfinch (Type A, 280 sq ft studio), Waxwing (Type B, 396 sq ft studio), Kingfisher (Type C, 491 sq ft 1-bedroom), Kestrel (Type D, 695 sq ft 2-bedroom), Sandpiper (Type G-1, 396 sq ft studio + garage), and Osprey (Type G-2, 376 sq ft studio + garage). Each plan has been reviewed and approved by the city's planning, zoning, and building departments, so homeowners can skip 4–8 weeks of design review and proceed directly to permit.
How much faster is a pre-approved plan than custom?
Permits typically clear in 3–5 weeks on pre-approved plans vs 8–12 weeks for custom. The savings come from skipping Boise's design review stage. Construction itself takes the same amount of time — the time advantage is entirely at the permitting office.
How much money do pre-approved plans save?
Roughly $8,000–$15,000 in architecture fees, plus 6–10 weeks of foregone rent or holding cost on rental projects. Construction cost per square foot is the same — the savings are entirely in the design and permitting phase.
Can I modify a pre-approved plan?
Yes for finishes, cabinets, counters, flooring, fixtures, paint, hardware — all fully customizable. No for structural footprint, exterior elevations, window placement, door placement, roof pitch, or siding type. Modifying any of those kicks the plan out of pre-approved status and back into full design review (losing the entire timeline advantage).
Which pre-approved plan should I pick?
Depends on your lot, budget, and use case. The Goldfinch (280 sq ft) is the cap-rate king. The Waxwing (396 sq ft) gives a real living zone. The Kingfisher (491 sq ft, 1 BR) is the landlord favorite. The Kestrel (695 sq ft, 2 BR) is the only pre-approved 2-bedroom. The Sandpiper and Osprey add a garage to a studio in different orientations. The free lot check pairs your specific lot with the best-fit plans.
Will a pre-approved plan fit on my lot?
About 70% of Boise lots in eligible residential zones can host at least one pre-approved plan without modification. Smaller plans (Goldfinch, Waxwing) clear more lots than larger plans (Kingfisher, Kestrel). The lot check verifies your specific parcel against all six plans and recommends the ones that actually fit your buildable envelope.
Do pre-approved plans work outside Boise?
The plans were created by the City of Boise but meet Idaho residential code, so they generally permit cleanly in Meridian, Eagle, Nampa, Kuna, Star, Caldwell, and Garden City. Each surrounding city runs its own permitting process — most align broadly with Boise but with city-specific setbacks, parking, and overlays.
What if no pre-approved plan fits my lot?
Custom design is the fallback. Custom adds $8–15k in architecture fees and 6–10 weeks of permitting time but solves the cases where the pre-approved set doesn't fit. About 30% of Boise lots end up custom — usually due to lot size, easements, hillside review, or historic overlays.
Free Lot Check · 24-Hour Response
Want to know which pre-approved plan fits your lot?
Submit your address. We'll run it against all six plans and come back with the ones that actually fit your buildable envelope.