A focused roofing workbench
RoofFolio is a free collection of six calculators for roofing measurements and material planning. It connects common-rafter geometry, roof pitch, surface area, roofing squares and field-shingle quantities through transparent formulas.
There are no accounts, purchases or quote requests in the toolkit. RoofFolio is free to use and is supported by advertising served by Google. Calculations run in your browser. Each tool publishes its method, worked example and assumptions alongside the input form.
What the numbers mean
The geometry uses right-triangle mathematics and constant-slope roof sections. Area conversion uses 1 sq ft = 0.09290304 m² and 1 roofing square = 100 sq ft. Length conversion uses 1 ft = 0.3048 m.
Rafter outputs describe reference lines. Material outputs describe area or whole bundles under your selected coverage and waste inputs. None is a structural design, construction approval or product recommendation.
Precision and accepted inputs
Calculations use JavaScript double-precision arithmetic. Most results display up to four decimal places; area multipliers show up to six. Transfers between tools use unrounded computed values. Unit changes retain approximately 13–15 significant digits; insignificant binary rounding may occur.
Feet and inches are separate fields. Inches accept decimals, simple fractions such as 1/2, and mixed fractions such as 1 1/2. If one component is filled, its blank companion means zero. Both blank means missing. Metric units are explicit. Negative, nonfinite and malformed values are rejected.
Optional fractional length display rounds to the nearest 1/16 inch. This is a display convenience, not a construction tolerance.
Bundle estimates round up to whole packages. A tolerance of eight scaled machine epsilons avoids a spurious extra bundle at a floating-point integer boundary; a material excess above that boundary still rounds up.
Numerical limits
These limits protect the interface and arithmetic; they do not represent construction or structural limits.
- Each entered length: at most 1,000,000 ft, equivalent to 304,800 m.
- Pitch: from 0:12 through 12,000:12. Angle entry must be below 90° and convert within that pitch range.
- Measured or calculated base roof area: at most 1 trillion sq ft. Direct projected-area entry also has a 1 trillion limit in its selected square-length unit.
- Roof area: up to 30 nonoverlapping sections.
- Chosen waste: 0% through 1,000%.
- Coverage entry: greater than zero, up to 1 billion in the selected coverage unit. Verified bundles per square: greater than zero, up to 1 million.
- Calculated bundle count: at most 1 trillion.
Nonzero quantities smaller than the display precision use scientific notation rather than showing a misleading zero. Check units and use an appropriate smaller length unit when needed.
Check the worksheet before relying on it
Confirm the measurement endpoints, units, selected modes and product coverage. Recalculate after editing: old results are marked out of date, and copying, printing and transfers are disabled until a successful calculation.
Geometric planning estimate. This does not size structural members or verify loads, connections, or code compliance. Verify structural and code requirements against local code or with a qualified professional.