A 40x40 barndominium is 1,600 square feet in a square footprint, and that shape is what makes it flexible: you can give the whole thing to living space, or split it into a home plus a shop. The square plan also keeps the structure efficient and the roof straightforward. Whatever you do inside, the all-in cost still hinges on land and site work far more than on the building itself, which is the recurring theme of our cost guide.
The defining feature of a 40x40 is the 40-foot width, which is deep enough to run two rows of rooms or to carve off a genuine shop bay. That depth is what separates it from the narrower 30-foot sizes and opens up the shop-plus-home layout people often want.
How people use 1,600 square feet
- A two- or three-bedroom home using the full footprint
- A two-bedroom home with a 40x12 to 40x16 shop bay
- An open great room made possible by the deeper span
- A home with a large attached garage instead of a shop
- A guest suite or in-law arrangement at one end
If you split the building, a common approach is to give roughly a quarter to a third of the footprint to a shop or garage and finish the rest as living space. That still leaves enough room for two bedrooms and an open living area on the conditioned side.
Cost drivers for a square build
A square footprint is structurally efficient, so the shell cost per square foot tends to be reasonable. The bigger variables are how much of the 1,600 square feet you condition and finish versus leave as shop space, since unfinished shop area costs far less per square foot than finished living area.
- Finished living area carries the highest per-square-foot cost
- Shop or garage area is much cheaper to leave unfinished
- A single slab pour covers both uses efficiently
- Plumbing concentrates in the living half of the building
- Land and site prep still dominate the total either way
Finish swing and siting
Because you can leave part of a 40x40 unfinished, the budget-to-high-end swing is wide. A modest build might finish 1,100 square feet and leave the rest as a raw shop, while a high-end version finishes the entire footprint with custom touches. Your land decides the rest; a serviced lot and a remote parcel produce very different all-in figures, as the examples on our Parker County cost page show.
Frequently asked: 40x40 barndominiums
- Can a 40x40 barndominium fit a shop and a home?
- Yes, and it is one of the most popular reasons to choose this size. The 40-foot depth lets you wall off a shop or garage bay at one end while finishing the rest as a two-bedroom home, all under one roof and on one slab.
- How many bedrooms fit in a 40x40 barndominium?
- Using the full footprint for living space, you can fit three bedrooms and two baths. If you carve out a shop, plan on two bedrooms in the remaining conditioned area.
- Is a 40x40 more efficient to build than a rectangular barndo?
- A square footprint uses materials efficiently and keeps the roof simple, so the shell cost is reasonable for the space. That said, the bigger cost drivers are still your finishes and your land, not the shape of the building.
- Does shop space cost the same as living space in a 40x40?
- No. Unfinished shop or garage area is far cheaper per square foot than finished, conditioned living space. That difference is why splitting the footprint can lower your overall budget.