A completed two-story barndominium with visible second-story windows and a small covered balcony above the entry porch.

2 Story Barndominium Floor Plans in New Jersey

Going up is how a barndominium fits a New Jersey lot. Where zoning limits how much of the lot a building may cover, a second floor doubles the living space on the same footprint. New Jersey's edition of the residential code changes two things that matter here: it allows a steeper, shorter stair than the national model code, and it caps an unsprinklered wood-framed house at two stories and 35 feet. The layouts below are concept plans to start the conversation, not permit drawings.

What actually changes with this feature

The look is the easy part. These are the decisions that follow from it.

The stair still needs width and headroom

New Jersey keeps the model code's other stair rules: at least 36 inches of clear width above the handrail, and at least 6 feet 8 inches of headroom measured from the line of the tread nosings. Where the stair lands matters as much as its length, because it sets how the upstairs hallway runs.

Every upstairs bedroom needs a window out

Each sleeping room needs an emergency escape and rescue opening of at least 5.7 square feet of net clear area, at least 24 inches high and 20 inches wide, with the bottom no more than 44 inches above the floor. Upstairs, that shapes the window schedule on the steel wall panels and should be fixed before the frame is ordered.

Guards on the landing and any balcony

An open side of a floor, landing or balcony more than 30 inches above the level below needs a guard at least 36 inches high, with openings that will not pass a 4-inch sphere. An open loft rail over a two-story great room falls under the same rule.

Two stories is New Jersey's cap for unsprinklered wood framing

New Jersey adds a section to its residential code limiting an unsprinklered house of unprotected wood-frame construction to two stories, 35 feet and 4,800 square feet per floor. With a sprinkler system throughout, the limit rises to three stories and 55 feet. Which construction type your frame is, and whether it needs sprinklers, is settled with the construction office when the sealed plans are prepared.

A completed two-story barndominium with visible second-story windows and a small covered balcony above the entry porch.
What New Jersey changes

New Jersey's stair is shorter than the model code's, and that frees floor space

The 2024 International Residential Code sets a maximum riser of 7-3/4 inches and a minimum tread of 10 inches. New Jersey's edition, in effect since August 17, 2026, replaces those with an 8-1/4-inch maximum riser and a 9-inch minimum tread. Take a 10-foot rise from the ground floor to the second floor. At the model code's limits that is 16 risers and 15 treads, about 12 feet 6 inches of run. At New Jersey's limits it can be 15 risers and 14 treads, about 10 feet 6 inches of run. Two feet of stair length is two feet of hallway or closet back, which matters on a narrow plan. A gentler stair is still allowed, and many owners choose one; the point is that the New Jersey minimum is not the model code's.

Common ways to build this

Three common ways to lay this out. Yours does not have to match one exactly — this is a starting point for the conversation, not a catalog.

Bedrooms up, living down

1,200 sq ft ground floor / 1,200 sq ft upper floor

A 30 by 40 footprint with the kitchen, living room, a half bath and laundry below, and three bedrooms and two baths above. The stair runs along one long wall so the upstairs hall is short and every bedroom gets an outside wall for its escape window.

Main-floor primary suite

1,500 sq ft ground floor / 900 sq ft upper floor

The primary bedroom stays on the ground floor for owners planning to stay long term, with two guest or children's rooms and a bath under the upper floor. The upper floor covers only part of the footprint, leaving a two-story ceiling over the living room with a guarded rail.

Garage below, house above

2 garage bays below / 1,100 sq ft living above

Vehicles and storage on the ground floor with living space over them. New Jersey's edition requires the dwelling space above a garage, and the structure that carries it, to have a one-hour fire-resistance rating, so this layout is detailed with the construction office from the start.

2-Story Barndominium: common questions

6 questions worth settling before this layout goes any further. If yours is not on the list, put it in the survey.

Is a two-story barndominium allowed in New Jersey?
Yes. The residential code covers detached houses up to three stories above grade plane, and New Jersey's own section caps an unsprinklered wood-framed house at two stories and 35 feet. Your municipality's zoning ordinance sets its own height limit, which may be lower.
How much space does the staircase take?
Less than under the model code. New Jersey allows risers up to 8-1/4 inches and treads as shallow as 9 inches, so a 10-foot rise can be climbed in about 10 feet 6 inches of run instead of 12 feet 6 inches. Add the 36-inch width and landings at top and bottom.
Do upstairs bedrooms need egress windows?
Yes. Every sleeping room needs an escape opening of at least 5.7 square feet of net clear area with its sill no more than 44 inches above the floor, on the second floor as on the first.
Why build up instead of out on a New Jersey lot?
On a suburban lot the zoning ordinance limits setbacks and how much of the lot buildings may cover. A second floor adds living space without enlarging the footprint, and it leaves more of the lot for the septic field or yard where one is needed.
Can the upstairs be a loft instead of full rooms?
Yes. An open mezzanine may cover up to one-third of the floor area of the room it sits in, with at least 7 feet of clear height above and below. An upper floor larger than that is planned as a full second story.
Does snow change a two-story design?
The roof has to carry the snow load for your site, which New Jersey sets through a site-specific hazard lookup rather than one statewide figure. The code's ice barrier provisions for roof coverings apply where January average daily temperatures are 25°F or less, and the State's Bulletin 07-3 names Sussex County as that area.

Want this layout tested against your program and your parcel? That is where a build actually starts.

Start with a concept layout

Tell us what you want to build and we will talk through this layout for your program: how it sits on your parcel, which municipal office permits it, and a realistic budget range. The permit plans themselves are sealed by a licensed professional, as New Jersey requires for a new house. That first conversation costs nothing.