Cost to Garage Conversion in Boise, ID (2026)

If you’re budgeting a garage conversion in Boise, most projects run $9,276-$27,827, 7% below the $20,000 national average. What moves that number most is usually one thing: HVAC - Mini-Split vs. Duct Extension. On its own it can swing the cost by $2,000-$5,000 for mini-split; $1,500-$3,500 to extend existing ductwork, so that’s the decision to slow down on before you sweat the smaller stuff.

Easiest place to save: Skip the full bathroom if you don't need rental income - adding plumbing adds $5,000-$12,000 to the project. A powder room (half bath) is a good middle ground at $3,000-$6,000.

In the Mountain West (where Boise sits): Higher costs in resort and metro markets; extreme temperature swings demand better HVAC.

$9,276-$27,827 in Boise

7% below the national average · 0.93x cost multiplier

Expect to pay $9,276-$27,827 for a garage conversion in Boise, about 7% below the national benchmark. The Mountain West region's contractor market and material costs account for most of this difference. The detailed breakdown below shows how budget, mid-range, and premium projects compare at Boise prices.

Cost Breakdown in Boise

Line ItemLowMidHigh
Materials$3,587$7,175$13,325
Labor$5,152$9,445$20,607
Permits$513$1,025$1,537
Total$9,252-7% vs. national avg$18,670-7% vs. national avg$37,006-7% vs. national avg

Budget

Basic single-car garage conversion to a bedroom or home office. Insulation, drywall, flooring (LVP), new window, HVAC extension to existing system, and electrical outlets. No plumbing, no structural changes. Functional but not luxury.

Mid-Range

Standard single-car garage to livable space (bedroom, office, or studio). Includes spray foam insulation, drywall, hardwood or tile flooring, HVAC mini-split for independent climate control, upgraded electrical, new exterior door, windows, and finishing work matching main house.

Premium

Double-car garage conversion to a full ADU, guest suite, or home gym with full bathroom. Includes plumbing rough-in and fixtures, kitchenette, mini-split HVAC, premium finishes matching the main home, proper egress windows, and full permit compliance for legal habitable space.

Material Options

Material prices below are national averages; availability in Boise may shift costs slightly.

MaterialCost/UnitBest For
Basic Office/Bedroom Conversion (No Plumbing)$25-$50/sq ftHome offices, gyms, game rooms, non-rentable guest spacesLowest cost, quickest completion, simpler permits
Full ADU Conversion (with Bathroom and Kitchenette)$75-$125/sq ftHomeowners wanting rental income or multi-generational livingLegal rentable unit generates income, adds significant home value
Single-Car Garage Studio$40-$80/sq ftHome offices, artist studios, small guest roomsGood balance of functionality and cost, manageable permit process
Two-Car Garage to Living Space$35-$65/sq ftFamilies needing a bonus room, larger ADUs, home gym + office combinationsMore square footage per dollar, room for multiple functions
Detached Garage Conversion$50-$100/sq ftRental ADUs, in-law suites, teen suitesMore privacy, often most ADU-permissible option

Other Projects in Boise

Boise Estimate

Typical Range

$9,276-$27,827

vs. National Average

7% below national

Cost Multiplier

0.93x

This 0.93x estimate prices Boise labor from BLS Occupational Employment and Wage Statistics (May 2025) and applies a lighter regional adjustment to materials and permits, which vary less by metro than labor does. Actual bids vary by contractor, project scope, and timing.

See national average costs →