Calculate wall studs, sheathing, roof rafters and roof sheathing for your shed build, plus material cost — metric or imperial.
On the Wall Framing tab, enter your shed's length, width and wall height, choose a stud spacing, and get a stud count, plate material plan, and wall sheathing sheet count. On the Roof Framing tab, choose a gable or skillion/lean-to roof, enter your dimensions, overhang and pitch, and get a rafter count, rafter length, and roof sheathing sheet count. Use the Cost tab with your own prices for an itemized material cost estimate that pulls from both tabs.
Wall stud count is calculated separately for each wall direction, then combined. Each wall's stud count is the number of on-center spacing intervals along that wall's length, plus one, based on your chosen max stud spacing.
You then add your own number of additional corner/framing studs on top of this base count — this calculator does not assume a fixed corner-framing method, since that varies by builder and shed design. A purchase allowance (5-15% is typical) is applied on top of the installed total to plan for cutting losses and mistakes. Door and window openings need their own additional framing studs, which you enter directly — this calculator does not design headers, king studs or jack studs for you.
Wall sheathing (plywood or OSB) is calculated from net wall area — gross wall area (perimeter × height) minus any door/window opening area you've entered — divided by your chosen sheet size, with a waste allowance for cuts around corners and openings.
Choose from common sheet sizes (1200×2400/2700/3000 mm or 4×8/9/10 ft) or enter a custom size — always confirm exact stock sizes with your local supplier.
Plate material (the horizontal boards at the top and bottom of the wall frame) is planned by the number of runs you need (for example, a double top plate plus a single bottom plate is 3 runs) and the stock length available to you. Because stock comes in fixed lengths, this calculator works out how many stock pieces each wall needs on its own — not just total linear length divided by stock length, which can understate real waste at wall ends and corners.
Rafter count depends on your shed's length and rafter spacing. A gable roof has two roof planes meeting at a ridge, so it needs a pair of rafters at each spacing interval; a skillion (or lean-to) roof has a single sloped plane, so it needs one rafter per interval.
Rafter length depends on the roof's horizontal run (half the width for a gable roof's each side, or the full width for a skillion roof, plus eave overhang) and the roof's pitch, expressed as a slope factor. A gable roof's end/rake overhang extends the roof past the gable end walls and adds to the roof area used for sheathing, without adding rafters.
Roof pitch is conventionally written as rise over a 12-inch run — for example, a "4/12" pitch rises 4 inches for every 12 inches of horizontal run. This is a ratio, so it applies the same way whether you're working in metric or imperial units for your other dimensions. If you enter a rafter stock length and your calculated rafter length exceeds it, the calculator flags this — it does not calculate splicing automatically.
Roof sheathing (the deck that roofing material is fastened to) is calculated the same way as wall sheathing: total roof area — accounting for the roof's slope and any end/rake overhang, not just the flat footprint — divided by your chosen sheet size, with a waste allowance. The roof sheathing sheet size is selected independently from the wall sheathing sheet size.
The Cost tab prices each material category separately: wall studs, rafters, plate material (per stock piece or per linear length), wall sheathing sheets and roof sheathing sheets, plus any optional additional cost lines you add (such as hardware or fasteners). This is a materials-only estimate — it doesn't include the finished roofing material (shingles, metal panels, etc.), siding, the floor or foundation, or labour, unless you add them yourself as an "Other cost" line.
Example 1 — Wall framing. A 10ft × 8ft shed with 8ft walls, 16in max stud spacing: the 10ft wall needs ⌈120÷16⌉+1 = 9 studs, so 2 long walls = 18 studs; the 8ft wall needs ⌈96÷16⌉+1 = 7 studs, so 2 short walls = 14 studs. Base field studs = 18+14 = 32 studs, before adding your own corner/framing studs and a purchase allowance.
Example 2 — Gable roof. The same 10ft × 8ft shed, 4/12 pitch, 1ft eave overhang, no end overhang, 24in rafter spacing: rafter length ≈ 5.27 ft, needing 12 rafters and a roof area of about 105 sq ft.
A common mistake is dividing total plate linear length by stock length instead of working out stock pieces per wall — this understates real waste, since offcuts from one wall usually can't be reused on another without extra joints. For roof framing, a frequent error is using the roof's flat footprint area instead of the sloped area — a sloped roof always has more surface area than the flat rectangle beneath it. Another mistake is treating a stud count as complete without adding your own additional studs for door and window openings, which this calculator does not add automatically.
This calculator estimates wall and roof framing material quantities from the dimensions, spacing, overhang and pitch you enter. It does not design headers, king studs, jack studs or lintels for openings, does not calculate rafter splicing, and does not include roof ridge boards, fascia, soffit, the finished roofing material, siding, the floor or foundation, hardware, or labour. It also does not perform structural sizing, load calculations, or building-code compliance checks — stud and rafter spacing options shown are commonly encountered layout choices, not verified-safe defaults for your specific project. For a code-compliant shed design, consult your local building department or shed plans engineered for your area.
This is calculated separately for each wall direction from your shed's length, width, wall height and stud spacing, then combined. Use the Wall Framing tab above with your dimensions for an automatic stud count including a purchase allowance.
Total lumber needs include wall studs and plate material (Wall Framing tab) plus roof rafters (Roof Framing tab). Enter your shed's dimensions on each tab above for an itemized quantity estimate.
Rafter count depends on your shed's length and rafter spacing; rafter length depends on the roof's run (half the width for a gable roof, or the full width for a skillion/lean-to roof), overhang and pitch. Use the Roof Framing tab above with your dimensions.
This depends heavily on shed size, framing materials, roofing, siding, and local labour/material costs. Use the Cost tab above with your own prices for studs, plates, rafters and sheathing for a material-only estimate specific to your project.
16 inches on-center and 400 mm on-center are commonly encountered layout choices for shed and residential wall framing; 24 inches / 600 mm on-center is sometimes used for lighter, non-structural sheds. These are not universal structural requirements — check your local building code or an engineer for load-bearing requirements that apply to your project.
This depends on your total wall and roof area (minus any door/window openings), divided by your chosen sheathing sheet size, plus a waste allowance. Use the Wall Framing and Roof Framing tabs above, where you can select a common sheet size or enter a custom one.
Stud spacing is the on-center distance between adjacent wall studs. Closer spacing (like 16 in / 400 mm) uses more lumber; wider spacing (like 24 in / 600 mm) uses less. Follow your local building code or shed plans for the spacing required for your project.
Roof pitch is usually expressed as rise over a 12-inch run (for example, a 4/12 pitch rises 4 inches for every 12 inches of horizontal run). Rafter length is the roof's horizontal run (plus overhang) multiplied by a slope factor calculated from this pitch. Use the Roof Framing tab above with your pitch to get this automatically.
You can optionally add each door/window opening's width, height and quantity on the Wall Framing tab, which reduces the net wall sheathing area. You also enter your own planned additional framing studs for each opening — this calculator does not design headers, king studs or jack studs automatically.
No - this calculator covers wall and roof framing materials only. For a concrete slab or footing, use the Concrete Calculator or Foundation & Footing Calculator.
A gable roof has two sloped planes meeting at a central ridge, common on larger sheds. A skillion (or lean-to) roof has a single sloped plane spanning the full width, common on smaller or simpler sheds. Select either option on the Roof Framing tab above.
No - the Cost tab estimates material cost only, based on the prices you enter for studs, plates, rafters and sheathing, plus any optional additional cost lines you add. Permits and labour are not included.