A compact 30x40 barndominium sized like a cabin in a clearing among tall ponderosa pines, with a covered entry porch.
30' x 40' · 1,200 sq ft footprint

30x40 Barndominium Floor Plans in Arizona

A 30x40 barndominium is 1,200 square feet on one level, the size most people picture when they want a simple, efficient home on acreage. It fits two bedrooms easily and three with care. In Arizona, a building this size lives or dies by its envelope: the short 30-foot ends should take the east and west sun, the entry needs somewhere for monsoon dust to stop, and the covered patio does as much for comfort as the interior layout. We design and build 30x40 barndominiums as kits or turnkey homes.

What actually changes at this size

The dimensions are the easy part. These are the decisions that follow from them.

Short ends to the sun

With the 40-foot walls facing north and south, only the 30-foot ends take the low east and west sun. That follows the Department of Energy's Building America advice to minimize east- and west-facing windows, and it lets the main living glass sit on the north or south wall under a porch roof.

A mudroom at the working door

Most 30x40 owners come and go through a side door, not the front. Putting a mudroom there, with the laundry beside it, keeps dust, boots and gear in one hard-floored room at the edge of the house instead of the kitchen.

Clear span, flexible rooms

A 30-foot span needs no interior bearing walls in a steel or post frame, so the partitions go where the plan wants them. That makes it easy to put the bedrooms at the cooler east end and the great room where the patio and view are.

The easiest kit to supply

A 30x40 is the most common barndominium kit size because the shell is simple: one span, one roof line, standard door and window openings. We supply the kit with drawings for the local permit, or we build the home turnkey.

A compact 30x40 barndominium sized like a cabin in a clearing among tall ponderosa pines, with a covered entry porch.
The entry matters

Monsoon dust storms are a yearly event, so the front door needs a buffer

The National Weather Service office in Phoenix lists dust storms among its storm event summaries year after year, including a massive dust storm on 25 August 2025 and strong winds and a dust storm across the Phoenix area on 19 August 2026. In a 1,200 sq ft home where the front door often opens straight into the living room, a small mudroom or vestibule, with a bench, hooks and a hard floor, catches the dust before it spreads. It costs little floor area, and it is far easier to draw in now than to carve out of a finished plan later.

How people actually split 1,200 sq ft

Common configurations at this footprint. Yours does not have to match one exactly — this is a starting point for the conversation, not a catalog.

Two bedrooms, two baths

1,200 sq ft, 2 bed / 2 bath

The primary suite at one end, the second bedroom and bath at the other, and an open great room and kitchen between them facing a covered patio along the north wall.

Three bedrooms, compact

1,200 sq ft, 3 bed / 2 bath

Three smaller bedrooms on the east half, a shared bath and a primary bath, and a tighter great room on the west half with the kitchen along the interior wall. Works for a family on a budget.

Living plus a shaded carport

1,200 sq ft living + a carport under the same roof

The roof extends past the west end over a carport, which shades the west wall and keeps vehicles out of the sun without the cost of an enclosed garage.

30x40 Barndominium: common questions

6 common questions about this footprint in Arizona. If yours is not on the list, ask it directly.

How many bedrooms fit in a 30x40 barndominium?
Two bedrooms and two baths fit comfortably in 1,200 square feet. Three bedrooms is possible if the bedrooms are compact and the great room is smaller. For three generous bedrooms, most people step up to a 30x50 or 40x50.
Is a 30x40 big enough to live in full-time?
For one or two people, yes. The open plan makes 1,200 square feet feel larger than a conventional house of the same size, and in Arizona a deep covered patio adds usable space for much of the year.
Which way should a 30x40 barndominium face in Arizona?
With the 40-foot walls to the north and south in most cases, so the 30-foot ends take the east and west sun. On a lot where the view or the access road points another way, shade the west side with a porch or carport.
Do I need a mudroom in a small barndominium?
It is worth it in Arizona. Monsoon dust storms happen every summer, and a small entry with a hard floor, a bench and hooks keeps dust out of the living space. In a 30x40 it can be as little as 40 to 60 square feet next to the laundry.
Can I buy a 30x40 barndominium as a kit?
Yes. A 30x40 is one of the most common kit sizes. The kit covers the frame, the roof and wall panels and the trim; the foundation, utilities and interior finish are separate. We supply kits with drawings for the permit, or we build the whole home.
Can a 30x40 barndominium be built in the high country?
Yes, with the structure drawn to the local figures. The City of Flagstaff's design criteria call for a 60 psf ground snow load and a 30-inch frost line, so a 30x40 there gets a heavier roof and deeper footings than the same plan in the low desert.

Want this drawn for your program and your parcel? That is where a build actually starts.

Start your plans

Tell us what you want to build and we will draw a 30' x 40' building for your program and your parcel: which way it faces, where the shade goes, and the snow load, wind speed and frost depth your city or county publishes. Where the building department requires it, an Arizona-registered engineer seals the drawings. Then we build it, or supply the kit if you would rather build it yourself. That conversation costs nothing.