Picking a size is the first real decision in any steel building project. Too small and you will wish you had gone bigger within a year; too big and you pay for space you do not use. Here is how to match the building to the job.
Start with the use, then add room to grow
Figure out what has to fit — vehicles, equipment, work areas, living space — then add 15 to 25 percent. Almost nobody regrets a slightly larger building; plenty of owners regret a tight one. Eave height matters too: lifts, RVs, and equipment need taller walls.
Popular sizes by use
- Two-car garage or backyard workshop: 24x30 (720 sq ft).
- Deep garage or small shop: 24x40 (960 sq ft).
- The all-purpose best-seller — garage, shop, or starter barndominium: 30x40 (1,200 sq ft).
- Shop with an office or living area: 30x50 (1,500 sq ft).
- Live-work barndominium or multi-bay garage: 30x60 (1,800 sq ft).
- Full barndominium, commercial shop, or barn: 40x60 (2,400 sq ft).
- Large commercial, warehouse, or agricultural: 50x80 and up.
Don't forget clearances
- Allow turning and door-swing room around vehicles and equipment.
- Size overhead doors for your tallest vehicle plus margin.
- Plan eave height for lifts, RVs, and mezzanines before you order.
- Check setbacks and lot coverage for your county before finalizing footprint.
Still unsure?
Tell AAIRE Co. how you will use the building and we will recommend a size and send a free quote. Because every building is custom-engineered, we can dial in the exact width, length, and eave height for your project — and your county's loads.
Frequently asked questions
What is the most popular metal building size?
The 30x40 (1,200 sq ft) is the best-selling size because it works as a four-car garage, a serious workshop, a starter barndominium, or a small commercial shop.
How much extra space should I plan for?
Figure out what must fit, then add about 15 to 25 percent. Owners rarely regret a slightly larger building, but a tight one is a common regret.