Equal-pitch hip roof geometry — rectangular plan length scenarios.
How does changing rectangular plan length affect equal-pitch hip roof geometry when the other inputs stay fixed?
What this decision changes
This measured quantity or supplied dimension enters the method on its stated unit basis. Other inputs stay fixed so its effect can be separated from net deductions, stock constraints or purchase rounding. Method basis: Equal pitches imply a ridge equal to plan length minus plan width. Unequal pitches, offset ridges, dormers and penetrations require separately measured planes.
The focus is specified rectangular plan length. All other shared inputs remain fixed for each evaluated range.
Evaluate your supplied alternatives
Start with your measured plan and selected product data. The initial values and range are illustrative. Each scenario changes only specified rectangular plan length; the other entered values stay fixed.
8 valid of 9 evaluated scenarios
Baseline: Four-plane roof area — 30 m². Rejected combinations remain visible below.
| Specified rectangular plan length | Four-plane roof area | Change from baseline | Use this scenario |
|---|---|---|---|
| 3.6 m | Plan length must be at least plan width. | ||
| 4.35 m | 21.75 m² | -8.25 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
| 5.1 m | 25.5 m² | -4.5 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
| 5.85 m | 29.25 m² | -0.75 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
| 6.6 m | 33 m² | 3 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
| 7.35 m | 36.75 m² | 6.75 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
| 8.1 m | 40.5 m² | 10.5 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
| 8.85 m | 44.25 m² | 14.25 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
| 9.6 m | 48 m² | 18 m² | Open in calculatorExact quantity breakdown
Geometry of a symmetric equal-pitch hip roof over the supplied plan, which must already include the intended eave projection. No slope, load, structure or drainage requirement is selected. |
Read the evaluated results
Read calculated demand, whole purchases and exact detail lines separately. This specific input may change quantity continuously, cross a purchase step or make the stated geometry or stock fit invalid.
- Replace every illustrative baseline measurement and selected product value with the inputs for your actual task.
- Enter a comparison range on the focused input's stated unit and quantity basis.
- Review rejected combinations and use the exact detail lines to distinguish measured demand from whole purchases.
- Open an evaluated scenario in the full calculator to save its original inputs and quantity breakdown to a browser material project.
Keep the comparison within scope
Compare measurements or already specified alternatives. Quantity sensitivity does not establish material suitability or construction requirements.
Equal pitches imply a ridge equal to plan length minus plan width. Unequal pitches, offset ridges, dormers and penetrations require separately measured planes.
Dimensions, quantities, prices, timing and product properties are supplied by you. This tool does not select construction specifications or assess structural, electrical or hydraulic suitability.
Only the listed samples are evaluated. Intermediate values, alternate constraints and global cutting optimality are not inferred from the graph.
Continue with this quantity method
Equal-Pitch Hip Roof Geometry CalculatorOther independent input decisions
Read the measurement and purchase guides
Quantity method and illustrative scenarios checked 6 October 2026. Methods and scope.