Inputs
Example Estimates
These examples use current defaults above and assume gable roofs with included floors.
| Size (L×W×H) | Roof | Foundation | Materials | Labor | Tax | Total |
|---|
Formulas Used
Floor area A = L × W
Perimeter P = 2 × (L + W)
Openings area = (doorCount × doorW × doorH) + (winCount × winW × winH)
Wall surface area S_walls = P × wallHeight − openings area
Sheets required (4×8) = ceil( (Area / 32) × (1 + waste%) )
Roof pitch factor F = sqrt(1 + (rise/run)^2) (gable only)
Roof plan = (L + 2×overhang_ft) × (W + 2×overhang_ft)
Roof area S_roof = Roof plan × F
Stud spacing ft = spacing_in / 12 (or mm/1000 × 3.28084)
Studs ≈ ceil(P / spacing_ft) + 8 corner studs
Plate lumber LF = 3 × P (double top + single bottom)
Gable rafters: pairs ≈ ceil(L / rafterSpacing_ft), length ≈ sqrt( (W/2 + overhang_ft)^2 + (pitchRise/pitchRun × (W/2 + overhang_ft))^2 )
Total rafter LF ≈ 2 × pairs × rafterLength
Lumber LF total ≈ studs × wallHeight + plateLF + rafterLF (+ floor joists if included)
Paint gallons ≈ ceil( S_walls / coverage )
Category costs = quantity × unit price (or per-square/per-sheet conversions)
Hardware = materials × hardware%
Waste applied per category where relevant
Labor = materials × labor%
Location multiplier applied to materials + labor
Tax = (materials × location + labor × location) × tax%
Contingency = subtotal × contingency%
Total = materials + labor + tax + contingency (with location multiplier where configured)
How to Use
- Choose units, enter shed dimensions, wall height, and roof details.
- Add doors and windows to subtract wall area for siding and paint.
- Select foundation, siding, and roofing types, adjusting prices as needed.
- Set allowances: waste, hardware, labor, taxes, multiplier, and contingency.
- Click Calculate to see quantities and a detailed cost breakdown.
- Use Export CSV or Export PDF to save your estimate.
FAQs
The calculator uses geometric takeoffs and unit prices you control. Real projects vary by site, weather, crew efficiency, brand selections, and local codes. Use contingency to cover remaining uncertainty.
This tool models labor as a percentage of material cost for speed. If you track hours, convert your expected hours×rate into an equivalent percentage and enter it in the Labor field.
Openings subtract directly from wall surface area, reducing sheathing, siding, and paint. Framing around openings is approximated with corner additions and waste factors.
Yes. Pick a type and override the price with your preferred brand’s current cost. Increase the waste percentage for brittle materials or detailed trim packages.
Permits, delivery, equipment rental, site prep, and utilities are typically project‑specific. You can roll these into contingency or add them as line items in the exported CSV/PDF.
Results
| Category | Qty | Unit | Unit Price | Cost |
|---|
- Materials $0
- Labor $0
- Tax $0
- Contingency $0
- Total $0
Notes
- Dimensions are inside-to-inside; overhang increases roof plan area.
- Adjust prices to reflect current local suppliers and brands.
- Increase waste for complex trim, valleys, or steep roof pitches.