Garage Conversion Cost Calculator 2026 — Room, Suite or ADU
Garage conversion cost for 2026: This Old House puts the national range at $9,659–$51,659. Price a 1- or 2-car garage line by line, adjusted for your state.
Garage Conversion Cost Calculator
Inside length × width. 100–1,000 sq ft.
Adjusts the labor share by local construction wages (BLS, May 2025).
homeprojectestimator.com · · https://homeprojectestimator.com/calculators/garage-conversion-cost/
Estimated garage conversion cost
$20,050
Typical range $12,850 – $27,200
Cost per sq ft
$45.57
Where the money goes
- Insulation, drywall, flooring, paint and trim $15.06–$23.05 per sq ft plus paint and trim$7,550 – $12,500
- Electrical: circuits, outlets, lighting $600 – $4,000
- Heating and cooling: ductless mini-split $3,100 – $5,000
- Shell work: close the door opening (wall + window) $1,300 – $4,200
- Building permit and inspections $300 – $1,500
National average. Pick your state and metro area to adjust the labor share (about 50% of this job) to local wages. Get three written quotes before you commit to a budget.
Component prices from This Old House (June 2026) and Fixr; see Sources below. Tile, built-ins, a sewer or septic connection, a separate utility meter and parking replacement are not included.
How to use this calculator
The calculator builds the price from the same line items a contractor's quote would have, so you can hold the two side by side.
- Garage size. Pick a 1-car or 2-car garage, or type the floor area. This Old House describes a single-car garage as about 200–240 sq ft and a two-car garage as about 400–440 sq ft; the presets use 240 and 440. To measure your own, take the inside length times the inside width at floor level. A garage that is 22 ft wide and 20 ft deep is 440 sq ft.
- What it becomes. Bedroom, office or living area is a dry room: no plumbing. Bedroom suite with a bathroom adds a full bathroom with its drain and supply lines. Studio / ADU adds a bathroom and a kitchenette, plus the higher permit and approval cost of a second dwelling unit.
- Heating and cooling. A ductless mini-split is the usual choice for a garage, because it heats and cools the room without touching the house system. Extending the house ducts is cheaper when the furnace has spare capacity and the ducts are close. Choose None only for a hobby room you will heat some other way.
- Insulate and drywall. Leave it ticked unless the walls and ceiling are already insulated and finished. Most attached garages have a finished wall on the house side and bare studs everywhere else.
- Replace the garage door. Removing the door and framing a wall with a window in the opening. Untick it if you plan to keep the door in place behind an insulated wall.
- Level the slab. Garage floors usually slope toward the door for drainage. Tick this if you want the floor flat or raised to meet the house floor.
- Your state. Adjusts the labor half of the estimate to local construction wages (see Prices by state).
Garage conversion cost in 2026
The national figures differ between sources because each one bundles a different scope into "conversion".
| Source | Typical range | Average |
|---|---|---|
| This Old House (June 2026) | $9,659 – $51,659 | $30,659 |
| Fixr (January 2025) | $20,000 – $75,000 | — |
| Angi data reported by Bob Vila (April 2024) | $6,012 – $27,090 | $16,199 |
Sources: This Old House, Garage Conversion Cost: Complete (2026 Price Guide), updated 06/12/2026; Fixr, Cost to Remodel a Garage, updated January 31, 2025; Bob Vila, Garage Conversion Cost: The Key Factors and Considerations, updated April 16, 2024.
Cost by what the garage becomes
| Use | This Old House (2026) | Fixr (2025) |
|---|---|---|
| Home office | $8,200 – $14,700 | $10,000 – $20,000 |
| Bedroom | $10,400 – $17,800 | $10,000 – $20,000 |
| Living room / living space | $12,300 – $19,600 | $7,000 – $75,000 |
| Home gym | $8,700 – $15,900 | $3,000 – $10,000 |
| ADU, studio or apartment | $31,500 – $73,200 | $50,000 – $75,000 |
| Bathroom | — | $15,000 – $30,000 |
| Kitchen | — | $20,000 – $40,000 |
Sources: This Old House, Garage Conversion Cost (2026 Price Guide), 06/12/2026; Fixr, Cost to Remodel a Garage, January 31, 2025.
Office, bedroom and living room conversions use the same trades and materials — insulation, drywall, flooring, wiring, heat — so the calculator treats them as one "dry room" option. The difference between them is mostly the window: a room used for sleeping needs an egress window under the building code.
Three priced examples
This Old House itemizes three projects, which are the clearest picture of where the money goes:
| Example | Size | Total | Largest lines |
|---|---|---|---|
| Basic home office | about 200 sq ft | $9,236 | Electrical $2,224, insulation and drywall $2,062, HVAC extension $1,900 |
| Mid-range bedroom | 280 sq ft | $20,729 | Electrical $3,336, mini-split $3,100, insulation and drywall $3,093, plumbing $2,500 |
| Premium ADU | 450 sq ft | $52,990 | Kitchen cabinets and appliances $10,500, electrical panel and wiring $5,004, structural work $5,000, bathroom $5,000 |
Source: This Old House, Garage Conversion Cost (2026 Price Guide), 06/12/2026.
What drives the price
- Plumbing. It is the line that moves a garage from the low five figures to the mid five figures. Fixr prices a bathroom inside a garage at $8,000–$25,000, and a kitchen at $20,000–$40,000.
- Floor area. Insulation, drywall and flooring scale with square footage. In This Old House's three examples, insulation and drywall came to $10.31–$11.05 per sq ft of floor, and flooring ran from $4.75 per sq ft (vinyl) to about $12 per sq ft.
- Heating and cooling. This Old House gives $300–$5,000. A duct extension sits at the low end ($1,900 in its office example), a mini-split higher ($3,100 in its bedroom example).
- Electrical capacity. This Old House puts the electrical work at $615–$4,021 and advises adding 25% to the first electrician's quote. An ADU that needs its own panel costs more: $5,004 in its ADU example.
- The floor. Raising or leveling the slab costs $600–$2,000 depending on square footage, per This Old House. Its bedroom example spent $2,100 on floor leveling and preparation.
- Whether it becomes a separate dwelling. An ADU needs its own kitchen and bathroom and a heavier permit process; This Old House's ADU example spent $2,000 on permits and approvals alone.
Cost breakdown
The result card splits the estimate into up to six lines:
- Insulation, drywall, flooring, paint and trim — $10.31–$11.05 per sq ft for insulation and drywall, $4.75–$12.00 per sq ft for flooring, plus $900–$2,340 for paint and trim (This Old House example lines). Tile, built-in cabinetry and soundproofing are not included.
- Electrical — $615–$4,021: new circuits, outlets and lighting. A separate subpanel or service upgrade can exceed this.
- Heating and cooling — $300–$1,900 to extend ducts, $3,100–$5,000 for a ductless mini-split.
- Shell work — closing the door opening with a wall and window, $1,300–$4,200, and leveling the slab, $600–$2,000. No source we could open prices the infill wall on its own; the range spans the windows-and-doors lines in This Old House's worked examples ($1,300 for its bedroom, $4,200 for its premium garage remodel). Ask for the framing, sheathing and siding match as separate items on any quote.
- Bathroom, or bathroom and kitchenette — $8,000–$25,000 for the bathroom (Fixr, January 2026). The kitchenette adds $10,500 for cabinets and appliances (This Old House ADU example) plus $1,500–$4,000 of plumbing.
- Permits — $300–$1,500 (Fixr); $1,000–$2,000 for an ADU (This Old House).
Not included: a separate utility meter, a new sewer or septic connection, replacement parking your city may require, structural repairs, and architect fees. Add a contingency of your own for anything found behind the walls.
Prices by state and metro area
Only the labor part of the estimate moves with the state. This Old House says "about half of what you pay goes toward labor" on a garage project, and Fixr's bathroom data also puts labor at 50%, so the calculator treats half the cost as labor. That half is multiplied by the state's construction wage index: the mean hourly wage for construction and extraction occupations in the state, divided by the national mean, from the U.S. Bureau of Labor Statistics' Occupational Employment and Wage Statistics for May 2025.
For the default 2-car bedroom conversion ($20,050 nationally):
| State | Wage index | Typical estimate |
|---|---|---|
| Washington | 1.26 | $22,650 |
| California | 1.20 | $22,050 |
| Texas | 0.84 | $18,450 |
| Mississippi | 0.78 | $17,850 |
Material prices vary much less between states, so applying the wage index to the whole bill would overstate the gap.
Metro areas spread wider than states: construction wages in Portland-Vancouver-Hillsboro, OR-WA are 26% above the national mean and in Dallas-Fort Worth-Arlington, TX 14% below it (BLS, May 2025). Pick your metro area under the state, and the labor share of the estimate moves by that percentage.
Permits, egress and parking
A garage conversion changes the room from storage to habitable space, which is why permits are required almost everywhere and why inspectors look at things a garage never needed: insulation, smoke alarms, a heat source and, in any room used for sleeping, an emergency escape opening. If the new wall in the door opening gets a window, size it as an egress window from the start; retrofitting one later means cutting the wall again.
Two other checks before you get quotes. First, zoning: some cities require a set number of covered or off-street parking spaces, and converting the only garage can trigger a requirement to replace it. Second, any HOA rules that govern the street-facing look of the house. Both are free to check and can end the project before you spend on drawings.
Garage conversion or home addition?
The garage already has a foundation, walls and a roof, which is why it is the cheaper way to add living space. The default here — a 440 sq ft dry room — works out to about $46 per sq ft. Fixr prices a finished home addition at $100–$300 per sq ft, and a 400 sq ft addition at $40,000–$120,000. The trade is the parking and storage you lose. Run both numbers with the home addition cost calculator before you decide.
How to compare quotes
Ask each contractor to price the same scope, split into the lines above. The most common reasons two garage quotes differ:
- One includes the door-opening infill and the other assumes the door stays.
- One prices a mini-split and the other a duct extension, or none.
- One includes floor leveling and a moisture barrier and the other lays flooring straight on the slab.
- One includes the permit and inspection fees and the other leaves them to you.
A quote that is far below the calculator's low figure usually leaves out one of these, not a cheaper way to do them. If you plan to borrow for the project, the renovation loan payment calculator shows the monthly cost of a home equity loan, HELOC or personal loan for the amount.
Sources
- This Old House, Garage Conversion Cost: Complete (2026 Price Guide) — national range $9,659–$51,659 and average $30,659; cost by space type; component ranges (electrical $615–$4,021, HVAC $300–$5,000, floor leveling $600–$2,000, permits); three itemized example projects (updated 06/12/2026). link
- This Old House, Garage Remodel Cost (2026 Pricing) — labor at about half the cost; windows and exterior door line $4,200 (updated 03/27/2026). link
- Fixr, Cost to Remodel a Garage — conversion range $20,000–$75,000, cost by use, permits $300–$1,500 (updated January 31, 2025). link
- Fixr, How Much Does It Cost to Add a Bathroom in 2026? — bathroom in a garage $8,000–$25,000, labor about 50% (updated January 22, 2026). link
- Fixr, How Much Does It Cost to Install a Ductless Air Conditioner? — a 12,000 BTU unit suits 400–600 sq ft (updated January 31, 2025). link
- Fixr, House Addition Cost — finished addition $100–$300 per sq ft; 400 sq ft $40,000–$120,000 (updated February 3, 2025). link
- Bob Vila, Garage Conversion Cost: The Key Factors and Considerations — Angi range $6,012–$27,090, average $16,199, $25–$75 per sq ft (updated April 16, 2024). link
- U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics, May 2025 — state construction wage index. link
Related
Frequently Asked Questions
How much does a garage conversion cost in 2026?
This Old House puts the national range at $9,659 to $51,659, with an average of $30,659 (updated June 2026). Fixr quotes $20,000 to $75,000 for a full conversion, and the Angi figures reported by Bob Vila run $6,012 to $27,090. The spread is mostly about plumbing: a dry room sits at the bottom, an apartment with a kitchen and bathroom at the top.
How much does it cost to convert a 2-car garage into a bedroom?
With this calculator's defaults — about 440 sq ft, insulation and drywall, flooring, new circuits, a ductless mini-split, the door opening walled in with a window, and a permit — the national estimate is $12,850 to $27,200, typically about $20,050. This Old House prices a garage bedroom at $10,400 to $17,800 and Fixr at $10,000 to $20,000.
How much does it cost to turn a garage into an ADU or studio apartment?
This Old House prices an ADU or studio apartment at $31,500 to $73,200, and Fixr puts an apartment or granny flat at $50,000 to $75,000. The jump comes from the bathroom and kitchen: Fixr prices a bathroom built inside a garage at $8,000 to $25,000, and This Old House's 450 sq ft ADU example spent $10,500 on kitchen cabinets and appliances.
How much does it cost to add a bathroom to a garage conversion?
Fixr's January 2026 data puts a bathroom in a garage at $8,000 to $25,000, against $10,000 to $35,000 for adding a bathroom in general. The drain is the hard part: garage slabs rarely have one, so the plumber has to cut a trench to reach the house sewer line. Labor is about half of the bathroom cost, according to Fixr.
Do I need a permit to convert my garage?
Yes — turning a garage into living space changes its use, so expect a building permit plus electrical and often mechanical and plumbing inspections. Fixr says the permit costs an average of $300 to $1,500. This Old House says ADU permits run $1,000 or more, and its ADU example spent $2,000 on permits and approvals.
What does it cost to heat and cool a converted garage?
This Old House gives $300 to $5,000 for HVAC on a garage conversion. Its office example extended the house ducts for $1,900 and its bedroom example installed a ductless mini-split for $3,100. Fixr's ductless guide rates a 12,000 BTU unit for 400 to 600 sq ft, which covers most two-car garages.
Is a garage conversion cheaper than an addition?
Usually much cheaper per square foot, because the slab, walls and roof already exist. This calculator's 440 sq ft default works out to about $46 per sq ft; Bob Vila's figure for finishing a garage is $25 to $75 per sq ft. Fixr prices a finished home addition at $100 to $300 per sq ft.