Like barns and condominiums, a barndominium can have a standard or unique design, layout, and size. You may also opt for distinct architectural features and functional spaces, depending on your needs. However, most of these possibilities are subject to the size of a barndominium.
The biggest size a barndominium can be is 4,200 sq ft (390 sq m) if you opt for a 60 x 70 feet (18.3 x 21.33 meters) steel building kit. The biggest size of a custom-built barndominium, with or without a kit, can be as much as 20,000 sq ft (1,858 sq m) and larger for two-story barndos if you want.
The biggest size a barndominium can be is subject to several limiting factors, such as available clear land, budget, building codes or zoning restrictions, etc. Also, the materials you choose will influence the architecture. Read on to know more about how big a barndominium can be.
Legally and technically, you can build a barndominium in the same way you or anyone would construct a traditional house. The building codes relevant to a house or residential property in your area apply to a barndominium, too.
Also, you can use the same materials to build a barndominium’s distinct structures as you might choose for constructing a conventional house, including but not limited to the following:
Therefore, in theory, the biggest size for a barndominium can be as large as a traditional house. The practical restrictions will still apply, of course. From the parcel of available clear land to the local building codes, everything will affect the size of a barndominium, just like your budget.
However, contemporary barndominiums aren’t exactly built or designed like a traditional house.
The most significant difference is the frame, followed by other structural components, such as the foundation and roof. The overall structural factor alone classifies barndominiums into two broad categories:
- Barndominium building kit: concrete foundation and steel frame.
- Custom-built barndominium: with or without a steel building kit.
A barndominium building kit isn’t the same as modular or prefabricated construction. The two have many differences, but one similarity has an inevitable impact on the size. Like prefab and modular units, a barndominium building kit has available sizes that you can choose from.
Suppose you want to build a single-story barndominium using a steel building kit. The probable sizes of such construction shall depend on the available kits. Let me use the example of one of the leading manufacturers of steel buildings, including barndominiums, General Steel.
General Steel has single-story barndominium steel building kits in the following sizes:
- 30 x 40 feet (9.14 x 12.2 meters)
- 40 x 60 feet (12.2 x 18.3 meters)
- 40 x 75 feet (12.2 x 22.86 meters)
- 60 x 60 feet (18.3 x 18.3 meters)
- 50 x 75 feet (15.24 x 22.86 meters)
- 60 x 70 feet (18.3 x 21.33 meters)
These options may lead you to presume that the 60 x 70 feet (18.3 x 21.33 meters) kit will be the biggest size–but that’s not the case. The floor plan or layout of this kit has only 60 x 30 feet (18.3 x 9.14 meters) of living space.
The rest is a garage space measuring 30 x 40 feet (9.14 x 12.2 meters). So, you get a lower net indoor area than a General Steel building kit measuring 60 x 60 feet (18.3 x 18.3 meters). You need the 60 x 70 (18.3 x 21.33 meters) size with the floor plan or layout of the 60 x 60 (18.3 x 18.3 meters) in this context.
That said, only the gross indoor area of a 60 x 70 (18.3 x 21.33 meters) barndominium will be around 4,200 sq ft (390 sq m). The net indoor area shall vary based on many factors.
The barndominium building kits of General Steel and other companies only account for the total size, not the floor plan and how you will design the interiors. These manufacturers will work with you and offer their expertise so that you can choose the best floor plan and overall architecture.
However, indoor walls and various other fixtures will reduce the available or usable floor area. The net indoor floor area is likely to be much less than the gross 4,200 sq ft (390 sq m) for a single-story barndominium built with a kit measuring 60 x 70 feet (18.3 x 21.33 meters).
The same principle applies to a 60 x 60 (18.3 x 18.3 meters) barndominium kit. The net area or size will be less than 3,600 sq ft (334.45 sq m). But this principle doesn’t apply to two-story barndominium kits of the same sizes, i.e., length x width.
The aforementioned standard sizes of steel building kits are available in different ceiling heights, so you can design a single or two-story barndominium.
The typical height of 10 to 14 feet (3 to 4.26 meters) is sufficient for the vaulted ceiling and roof of a single-story barndominium. If you want to build a two-story barndo, you must increase this height to at least 21 feet (6.4 meters). The length and width can be the same as above.
Let me use the example of a rectangular overall floor layout of a 60 x 70 feet (18.3 x 21.33 meters) kit. The gross indoor area can be up to 8,400 sq ft (780.4 sq m) for such a two-story barndominium. The net area will be significantly less, especially after you consider the stairs and more indoor walls.
Furthermore, an open living space with high ceilings and similar floor plans or layouts will have an enormous impact on the net indoor area or total usable space in a two-story barndo.
However, note that barndominiums don’t have to be rectangular. You can even build a circular barndo if you like. I’ve discussed barndominium shapes in a separate guide called Do Barndominiums Have to Be Rectangular?
Suppose you don’t want a mezzanine or second story above the open hall, living, and dining area. In that case, you will be letting go of that entire portion of space, which could be some hundred to more than a thousand square feet.
On the flip side, you can save some space if you go for a spiraling staircase instead of the more conventional stairs. But the partitions or non-load bearing walls will inevitably affect the usable space.
Thus, the biggest size a barndominium can be if you have a two-story design for a 60 x 70 feet (18.3 x 21.33 meters) steel building kit will be substantially short of the 8,400 sq ft (780.4 sq m) area on paper.
Also, I should mention that the second story doesn’t have to be a steel building kit, like the main frame and secondary structures, including the roof. You can use wood and other materials for the partitions and non-load-bearing walls.
Steel is an expensive material for indoor fixtures without any major advantages over other and more traditional options, such as wood. Besides, you won’t need to restrict your design and layout for the first or second story to a handful of standard sizes of the various manufacturers.
The standard building kits for barndominiums don’t lack customization per se. You can decide on everything about the interiors to personalize your barndo, including the floor plan or layout. But the size of the exterior or perimeter is a given due to a chosen kit’s length and width.
There are two ways to plan and build a custom barndominium. You may design everything to build a barndo from scratch with the materials you prefer. Alternatively, you can customize a barndominium building kit and buy it from a manufacturer.
Let me use the example of Worldwide Steel Buildings to give you an idea of the biggest size a barndominium can be with a kit.
Worldwide Steel offers an online 3D Building Designer for owners to customize a barndominium with the following maximum dimensions:
- Width: 100 feet (30.5 meters)
- Length: 200 feet (61 meters)
- Height: 24 feet (7.31 meters)
So, you can custom-build a 100 x 200 feet (30.5 x 61 meters) barndo with two stories using a Worldwide Steel Building kit. If you go for one story, the maximum gross floor area is 20,000 sq ft (1,858 sq m). If you opt for a two-story barndo, you can get a gross usable area of 40,000 sq ft (3,716 sq m).
Of course, the net livable or usable area of the potentially biggest size of such a barndominium will practically be much less due to various fixtures, including but not limited to the following:
- Doors and windows: sizes, types, etc.
- Electrical and plumbing installations
- HVAC and other such fixed appliances
- Insulation, drywall, flooring materials, etc.
- Stairs, partitions, non-load-bearing walls, etc.
If you don’t use a barndominium kit, you aren’t restricted to any generic or standard sizing of the companies like General Steel. Also, the customizations of Worldwide Steel Buildings have some limitations, albeit the scope is more than sufficient for almost anyone in the context of size.
You can build as small or large a barndo as you can or want from scratch. Here’s a video tour of a 10,000 sq ft (929 sq m) barndominium in Texas:
Suppose you have no shortage of available land. And you can pour concrete over the land to prepare the required foundation for a barndominium. In such a scenario, a financial compulsion or building code restriction might prevent you from opting for a palatial barndo.
Otherwise, there’s no limit to the biggest size a barndominium can be, except for what you need.
You could get a kit to build a single-story barndominium of around 20,000 sq ft (1,858 sq m) or a two-story barndo with a similar perimeter offering up to 40,000 sq ft (3,716 sq m). In either case, you can optimize the floor plan to maximize a barndominium’s size.
You could get a mezzanine level if you cannot or don’t want to build a full-fledged second story. An additional level, although partial, can serve as a reading room, workspace, etc. Likewise, you can explore a plethora of layouts to get the most out of the available area with an apt floor plan.
You can check out these floor plans of J+E Renderings if you want. If you go with General Steel or Worldwide Steel Buildings, you will get to consult an expert project manager to assist you in selecting a design and layout that will maximize the available floor area or the barndo’s net size.
Also, there are other ways to optimize a barndo’s design to maximize the livable or usable floor space. For example, you can have a basement under a barndo. The only requirement is that the concrete pier or slab at the ground level should be the foundation for a steel barndominium.
Having said that, the biggest barndominiums have significant extra costs and project duration issues that you must be aware of. These effects also apply to two-story barndos and those with a basement, irrespective of the size.
An enormous barndo is obviously costlier than a modest barndominium, but the impact on cost depends on how you choose to optimize the design for maximum floor space.
For instance, opting for a larger barndo size in terms of length and width will increase the cost of material, not only the steel for the frame and roof but also drywall, insulation, etc. The effect is similar if you go for a two-story barndo. So, you will have to compare the costs specifically.
Likewise, a two-story barndo will require extra investment in heating, cooling, and plumbing essentials. A basement under a barndo isn’t necessarily a more affordable alternative unless it is already there.
Apart from these financial factors, the most significant disadvantage of the biggest barndos is a lack of demand in the resale market. A massive barndominium is likely to be a tough sell in the foreseeable future. If you won’t consider selling anytime soon, the size isn’t an issue for you.
All the other advantages of a barndominium apply equally to small and large sizes. For instance, you will get a 50-year structural warranty on barndominium steel building kits from General Steel and Worldwide Steel Buildings.
Additionally, companies like General Steel offer the following warranties:
- 40-year paint warranty
- 25-year roof warranty (galvalume)
- 20-year roof warranty (standing seam)
All such warranties are regardless of the size of a barndominium made by these companies.
Like a barn or condominium, you can build as big a barndominium as you want unless you can’t due to financial, legal, structural, or other technical issues. If you can’t go for a barndominium of the size you want, try to optimize the indoor space to extract as much livable area as possible.