Garage Apartment Steel Buildings, Engineered for Living Space From the Start
Put the apartment above the bays or beside them. Northcraft can supply the second floor with the building, designed into the engineering from day one.
50-Year Paint Warranty, 50-Year Rust Perforation Warranty, 60-Year Structural Warranty, and Lifetime Warranty on Hardware — all transferable to the next property owner.
Get Your Customized Quote
- No obligation — we’ll send the price, not a salesperson to your door.
- Engineered drawings stamped for your state.
- 60-Year Limited Structural, 50-Year Limited Paint, 50-Year Limited Rust Perforation, and Lifetime Limited Hardware warranties.
- Delivered nationwide, all 50 states.
C-Channel or I-Beam Framing • Living Space Above or Beside • 60-Year Limited Structural Warranty • Nationwide Delivery
How Buyers Configure a Garage Apartment Building
Same engineered frame, four common ways to split living space from the bays.
Apartment Above the Bays
Built over the garage bays, this keeps the ground footprint smaller. Northcraft can supply the second floor (mezzanine) with the building, engineered for the floor load and the stair opening from the start, so tell your estimator this is the plan before drawings begin.
Side Wing Beside the Bays
A ground-level wing next to the bays skips the stair opening and the floor-load engineering a second story needs. It takes more ground footprint instead, with its own exterior wall running along the side of the garage.
In-Law Suite
Planned for a parent or an adult child, an in-law suite can use either layout, over the bays or beside them. What changes is how you separate the entrance and what you tell your estimator about who the space is for.
RV or Boat Bay With Living Quarters
A tall bay for an RV or boat sits next to a smaller living unit, or the living unit goes above it as a second story. The bay's clear height for the vehicle and the apartment's floor plan both belong in the same set of drawings.
Check the Rules on a Second Home Before You Plan One
Your local building department will usually treat a garage apartment as a second dwelling unit, often called an accessory dwelling unit or ADU, not as part of the garage. Rules on second units vary widely from one city or county to the next, and the rule for a lot across town may not be the rule for yours.
Ask your building department these questions before you settle on a floor plan:
- Is a second dwelling unit allowed on this lot at all?
- Is there a size cap on the unit?
- Does a family member have to live there, or can it be rented out?
- Does the lot need extra parking to qualify?
- Does the unit need its own address?
Once the rules are clear, plan how the apartment separates from the garage itself. A garage holds exhaust, fuel vapors and fire risk that living space should not share air with. Your local code sets the fire rating for the wall and any door between the two, so ask rather than guess.
A door straight from the garage into the apartment has to meet code, usually a solid or fire-rated door that closes and latches on its own, and many codes don't allow one into a bedroom. Ask your building department which door it requires. Giving the apartment its own outside entrance avoids a direct opening from the garage.
Backed By Real Warranties
YEAR LIMITED PAINT WARRANTY
YEAR LIMITED RUST PERFORATION WARRANTY
YEAR LIMITED STRUCTURAL WARRANTY
LIMITED HARDWARE WARRANTY
All four warranties are transferable to the next property owner. Every building ships with code-compliant stamped engineering for the delivery state.
* Warranty coverage is subject to applicable warranty terms, conditions, limitations, and exclusions. Complete warranty details are available before you place an order and included within the applicable purchase documentation.
Frequently Asked Questions
Does the building come with the apartment's interior finish?
No. Your local contractor handles the interior finish-out: insulation, drywall, plumbing, electrical and flooring. Plan the plumbing and electrical rough-ins before the slab is poured. The second floor itself is different: Northcraft can supply it with the building.
Can the apartment go above the garage, or does it have to be beside it?
Either. An apartment can sit above the garage bays as a second story or beside them as a ground-level wing. A second story has to be designed into the engineering from day one, so tell your estimator that's the plan on your first call, before drawings start.
Can Northcraft supply the second floor?
Yes. Northcraft can supply a second floor (mezzanine) with any of its buildings. Tell your estimator where the apartment goes on your first call, so the floor is designed into the building's engineering from the start.
Is a garage apartment allowed on my property?
That depends entirely on your local zoning and building code, since a garage apartment is usually treated as a second dwelling unit. Some places allow one on any residential lot, others cap the size or restrict who can live there, and some don't allow one at all. Confirm with your local building department before you plan the layout.
How do I separate the apartment from the garage for fire safety?
Your local code sets the rating for the wall and any door between the garage and the apartment, so confirm the requirement with your building department rather than guess. A connecting door usually has to be solid or fire-rated and close and latch on its own. Giving the apartment its own outside entrance avoids a direct opening from the garage.
Do I need a permit for a garage apartment?
Most jurisdictions require a permit for the structure itself, plus a separate review for adding a residential living unit on the property. We provide the stamped engineering drawings your local building department will ask for. The second-dwelling-unit approval runs through your local process.
Can I add the apartment later, after the garage is already up?
You can lengthen a steel building later by adding more bays, which can make room for a ground-level apartment on the end, with its own engineering, foundation and permits. The width and the height can't be extended later, so settle those, and any second floor, in your original order. Tell your estimator now if there's any chance you'll want the apartment later.
How long does a garage apartment building take from order to delivery?
Typically 45-60 days from order to delivery. Your estimator confirms a real date range once your drawings are finalized.
Get Your Garage Apartment Customized Quote Today
Tell us where the apartment goes and we design it into your building. No obligation.
Call: (888) 460-9294 | Email: Estimating@Northcraftsteel.com
Get Your Customized Quote