About the Hip Roof Calculator
Surface area, ridge length and hip rafter length for a four-slope hip roof.
Also known as: hip roof area, four slope roof, hipped roof calculator.
How to use this calculator
- Enter building length, building width, roof pitch, overhang.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
area = 2 trapezoids + 2 triangles, all on the slope plane
Worked example
Using the values pre-filled in the calculator above:
- Building length = 14 m
- Building width = 8 m
- Roof pitch = 30 °
- Overhang = 0.4 m
the calculator returns:
- Total roof area: 150.388 m²
- Ridge length: 6 m
- Common rafter length: 5.0807 m
- Hip rafter length: 6.7211 m