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Product Description
Our 30 x 40 prefab buildings deliver 1,200 sq ft of clear-span interior space for a four-car metal garage with a shop, a small warehouse or auto shop, or a three-bedroom barndominium or shop house with an attached double garage. The compact footprint works well on most lots and gives you flexible interior layout options.
Popular 30×40 building applications by height:
30x40x10 metal building 2, 3, or 4 car garage with workshop space 30x40x12 metal building 2-4 vehicle auto shop, two stall horse barn 30x40x14 metal building RV garage, maintenance shop with lifts 30x40x16 metal building Two-story, 3-bedroom barndominium or shop house 30x40x20 metal building Heavy equipment machine shed or small inventory warehouse Each building package includes pre-cut steel I-beam primary framing, secondary purlins and girts, 26 ga PBR roof and wall panels, and a complete trim package. The number, width, and height of framed door openings are fully customizable, allowing you to configure wide front-facing bays, side-access doors, or a mix of vehicle and personnel doors. With a 30' wide steel building, you get two spacious 20' wide bays that can be configured to suit your specific access requirements.
Allow at least 2 ft of clearance between the top of the tallest door and the eave height; for example, a 12 ft-tall RV door needs a 14 ft eave.
Unlike light-gauge tubular buildings and pole barns, our trussless red iron PEMBs are custom-engineered to meet or exceed local codes for snow, wind, and seismic loads, giving a clean permitting path for barndominiums and other occupied uses while adding long-term property value and reduced insurance premiums.
How much does a 30×40 metal building cost?
The average installed cost of a 30 x 40 metal building is $32,400 to $48,000. This includes the building kit package at $18-$22/sq ft, the concrete slab foundation at $4-$8/sq ft, and construction at $5-$10/sq ft. Optional upgrades such as insulation, additional doors/windows, and interior finishing should also be budgeted for.
What are my options for installation?
When it comes to installation, you have several options for constructing a metal home or other metal buildings, depending on your expertise and budget:
DIY: Our buildings are ideal for those with some construction experience. They come with detailed instructions and numbered parts for quick and easy assembly.
Self-Build: You manage the entire construction project and act as the general contractor, hiring sub-trades for each stage, from concrete to construction and finishing.
General Contractor (GC) builds: A general contractor manages the entire project, ensuring structural integrity and compliance with local codes.See our 30x40 building construction page for more details.
Please note: for a 30x40 steel building package (approx weight 3-4 tons), a telehandler (teleforklift) with at least 5,000 lb capacity will be required at the jobsite to offload the primary and secondary steel framing components. Also, subject to suitable access, delivery may not be available in all locations - check first with your building specialist.
Start with this 30×40 building package as your base design, then customize door layouts and clearances, windows, lean tos, insulation, and color combinations.
Get guaranteed fast delivery with 20 shipping points, including California, Texas, Georgia, Florida, Oklahoma, and Ontario, Canada.
What are my options for finishing the interior of a 30x40 pre-engineered building?
Insulation is the most critical first decision; closed-cell spray foam is the top performer for steel buildings, bonding directly to metal panels, eliminating condensation, and serving as a vapor barrier in a single step. Fiberglass batt is cheaper but requires a separate vapor barrier and leaves thermal bridging gaps at the girts.
For garages & workshops: walls, OSB/plywood sheathing over metal studs is the most practical choice, easy to hang shelving, mount tools, and patch.
For barndominiums & shop houses: frame interior stud (steel or lumber) walls independently of the steel frame, insulate, then drywall. This also gives you space to run electrical and plumbing cleanly.
Pro tip for homes: order straight columns, not tapered, if you plan on interior wall finishes, tapered columns eat usable floor space and complicate framing. Be sure to specify these when placing your order.
Use
Best Wall/Ceiling Finish Insulation Floor Garage Exposed or painted steel liner panels Fiberglass batt or reflective foil (budget) Sealed/epoxy-coated concrete Workshop OSB or plywood over metal studs Closed-cell spray foam (R-15+) Sealed concrete Barndominium living area Drywall over steel stud framing Closed-cell spray foam (R-21+) LVP, tile, or polished concrete 
Request competing quotes from vetted local suppliers to fine-tune specs and timelines before you buy.
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Specifications
30x40 Building specs:
Width: 30 feet Length: 40 feet Eave height: 12 feet Square feet: 1,200 Sq Ft (clear span without posts or columns) Roof style: Gable Roof pitch: 3:12 Walk doors: 1 Overhead doors: 1 Windows: 6 Wind load: 70-160 mph Snow Load: 10-110 psf -
What's Included
Packages include:
- Steel I-Beam framing
- Steel roof & wall panels (26ga)
- Complete trim package
- Two framed door openings
- Foundation anchor bolt plans
- Engineer stamped plans
- Building delivery
- Installation instructions
- All bolts, flashing & sealants
I-beam steel framing
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Features
Benefit from:
- Bolt-up construction
- Primary framing: Steel I-beams
- Second framing: steel purlins & girts
- PBR metal wall & roof panels: 24 or 26 ga.
- Trussless roof design
- Clearspan widths to 300'
- Bay spacing: 20', 25', and 30'
- Widths: 30' to 300'
- Heights: 10' to 40'
- 30+ year warranty
- Fast, free delivery
- Fast build time
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Customization
Custom options:
Doors - Choose overhead doors, rollup, sliding or bifold doors.
Roof profile & pitch - Adjust the gable roof pitch or select a single-slope, gambrel, or monitor profile
Insulation - Opt for vinyl-faced fiberglass, spray foam, or insulated metal panels (IMPs).
Structural upgrades - Add porches, overhangs, a carport lean-to, or a mezzanine for loft storage.
Color options - Mix and match 22 standard colors for roof, walls, trim, and wainscot. Download our color chart.
BuildingsGuide PBR metal panel color chart
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Exclusions
Items not included:
- Permits
- Foundation
- Installation
- Insulation
- Interior build out
30x40 Metal Building
From US$ 24,000.00
A 30×40 metal building provides 1,200 sq ft of clear-span (column-free) space for a garage, shop, horse barn, or small barndominium. Design your layout from scratch, choose wall heights from 10' to 25', add a lean-to for covered storage, or build out a mezzanine loft level.
Every kit is custom-manufactured to your specs using American red iron framing. Fully customizable with your choice of doors, windows, colors, and structural upgrades.
Most 30x40 steel buildings are erected in just 2–4 days.
Dimensions: 30'x40' (Available heights - 10'-30')
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Frequently asked questions
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Do I need engineered plans and permits for a 30x40 steel building?
In most cases, yes. A 30×40 building (1,200 sq ft) exceeds the small-structure exemption in virtually every US jurisdiction. Most counties require a building permit and engineer-stamped drawings showing local wind, snow, and seismic loads. Always check with your local building department first, as rules vary by county.
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What roof pitches are available for 30 by 40 buildings?
All 30-by-40 bolt-up buildings come with a standard 2:12 roof pitch, although pitches ranging from a shallow 1:12 to a steeper 4:12 are available as options. Some of our suppliers can provide custom roof pitches of 5:12 and 6:12.
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How does the cost of a metal 30x40 building compare to a stick built structure?
A 30×40 metal building runs roughly $32,000–$48,000 turnkey (shell + slab + labor), or about $27–$40/sq ft installed — typically 30–50% less upfront than comparable stick-built construction, which averages $60–$100+/sq ft for a finished structure. Steel also wins in the long term: lower maintenance, lower insurance, and a 50+ year lifespan versus 25–40 years for wood.
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How much does a 30x40 concrete slab cost?
On average, a 30x40 concrete lab will cost $7,200. Typically, a concrete slab will cost between $4 and $8 per square foot (based on a nationwide average) for both materials and labor. The final price will depend largely on your building's location, as costs vary from coast to coast. Be sure to check current pricing with two or three local professionals.
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What financing options are available for metal buildings?
Here are the most common options for financing a new building.
- Consider home improvement loans for smaller projects, such as small metal shop buildings, standard garages, or shops.
- Home Equity Line of Credit (HELOC) is more flexible and has competitive rates, but you must use your home as collateral.
- Construction loans are ideal for larger residential and commercial projects.
- Farm credit for agricultural and farm building projects is the final option.
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Is a 30 × 40 building big enough for 2 cars plus a small workshop?
Yes, comfortably. A 30×40 (1,200 sq ft) building gives you enough room for two standard vehicle bays (each ~10×20 ft) plus a dedicated 400–500 sq ft workshop area. Most buyers find it ideal: two 10-ft wide garage doors fit easily on the 40-ft wall, leaving the remaining depth for workbenches, storage, and tools.
Why choose us?
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Since 2004, over 200K buyers have saved an average of 28% on their project with our multiple quote service.
Proudly serving customers in the United States & Canada for over 20 years.
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