Calculators / Sheds, pergolas and gazebos
Shed plans for your size
Put in the size, walls, door and roof. You’ll get each framing member sized from the building code’s tables, and a list of what to buy.
Updated · How we check our numbers
Shed framing plan
10 × 12 ft shed
2x8 floor joists, 2x4 walls at 24 in, a 2-2x6 door header and 2x4 rafters at 6/12, in spruce-pine-fir No. 2.
- Floor joists
- 2x816 in o.c.
- Rafters
- 2x420 psf live
- Header
- 2-2x65 ft door
- Floor area
- 120 sq ftunder 200 sq ft
Estimate for planning only, not professional advice. Check the manufacturer’s instructions, your local code and a licensed professional before you buy, build or install. Use at your own risk. Terms.
The foundationGravel, blocks, skids or slab for this size.
rafter span = 10 ft ÷ 2 = 5 ft horizontal; length × 1.1 for 6/12
Framing and cut list
Spruce-pine-fir- 10 floor joists, 2x810 ft each, 16 in on center, plus 2 rim joists 12 ft long; table allows 12¼ ft12 boards
- Floor sheathingSingle-floor panels rated 16 o.c. (19/32 or 5/8 in), Table 503.2.1.1(1)4 sheets
- 30 wall studs, 2x48 ft walls, 24 in on center (Table 602.3(5)), with extra at corners and the door30 × 8 ft
- Plates, 2x4One bottom and a double top plate all the way round132 ft
- Door header, 2-2x65 ft opening, building up to 12 ft wide (Table 602.7(1))spans 6 ft
- 20 rafters, 2x410 pairs, 16 in on center, 80½ in long with a 12 in overhang; span 5 ft (Table 802.4.1(1))20 × 7 ft
- Ridge boardOne size deeper than the rafters, 12 ft12 ft
- Roof sheathingBoth slopes6 sheets
- Wall sheathing or siding panels44 ft × 8 ft, less the door10 sheets
Sizes from the IRC tables as adopted in Ohio; counts are a buying estimate. Add 10% for waste.
The rafter tables assume ties or ceiling joists low in the roof, at the top of the walls. Ties set higher than that shorten the allowed span (the tables’ footnote).
Ohio, like many states, skips the permit for a one-story shed up to 200 sq ft but still expects it to meet the code. Your local code and snow load may differ; check with your building department.
How we work it out
Every size comes from the International Residential Code's framing tables, as Ohio adopted them (its code site is free to read). Floor joists span the width: Table 502.3.1(2) at 40 lb per sq ft live load. Walls are 2x4 at 24 in on center, which Table 602.3(5) allows up to 10 ft tall when they carry only a roof; the code doesn't allow 2x3 in exterior walls.
rafter span = width ÷ 2, measured level · header: the doubled 2x that spans the door
Rafters come from Table 802.4.1(1) for a 20 psf roof live load, or 802.4.1(3) for 30 psf of ground snow, and the door header from Table 602.7(1). Floor sheathing is a single-floor panel rated for your joist spacing.
Many places let a one-story shed of 200 sq ft or less go up without a permit, but Ohio, for one, still expects it to meet the code. If you get lots of snow or your building department uses different loads, the sizes change.
Where the numbers come from
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Shed
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