Table of Contents
What Is a Pyramid Roof?
A pyramid roof is a type of hip roof where all four sides slope upward and meet at a single point, forming a shape that resembles a pyramid. The hips on a typical hip roof rise to meet at the ridge, with the two hips on one end meeting each other at the ridge, and the two hips on the other end meeting each other at the ridge, and the two sets of hips separated by the length of the ridge. In the case of a pyramid roof, the ridge is just one point (the apex), and all four roof hips converge and meet each other at the apex.
This roof style is commonly used on smaller structures like gazebos, cabins, and some smaller homes.
A pyramid roof requires a square base, where all four sides are the same length.
What This Calculator Does
This pyramid roof calculator helps you determine key roof dimensions and surface area based on the geometry of a pyramid. You can choose between:
- USA units (feet and slope input in “X in 12” format)
- Metric units (meters and slope input in degrees)
You can also choose to input either the roof height or the roof slope, depending on the information you have.
The calculator provides the following results:
- Total roof surface area – the combined surface area of all four triangular roof sides
- Area of each side – the surface area of one of the four identical roof planes
- Roof footprint area – the horizontal area the roof covers (base length × base width)
- Roof vertical rise (height) – the distance from the height of the eave vertically to the height of the apex
- Roof surface slant height – the diagonal length from the midpoint of an eave to the apex measured along the face of the roof
- Roof slope – the incline of the roof’s surface, expressed in both degrees and roof pitch format (X in 12)
- Roof pitch multiplier – the multiplier used to convert horizontal roof footprint area to sloped surface area. Read more about roof pitch multipliers.
- Hip rafter length – the diagonal length of one hip rafter from a corner to the apex
- Combined length of all hips – the total linear length of the four hip rafters
- Hip rafter slope – the pitch of the hip rafters, expressed in both degrees and roof pitch format (this will be shallower than the roof pitch)
How to Use the Calculator
1. Choose a unit system:
Select either USA (feet and slope in “X in 12” format) or Metric (meters and slope in degrees). The calculator accepts decimal values.
2. Choose an input method:
- Select Height Input if you know the vertical rise from eave level to apex level.
- Select Slope Input if you know the roof slope:
- In USA mode, enter the X in “X in 12” format.
- In Metric mode, enter the slope in degrees.
3. Enter the length of a side:
- Base Length of a Side: Enter the horizontal length of the eave edge on one side of the roof.
4. Enter the height or slope value:
- If you selected Height Input, enter the straight vertical rise from the eave level to the apex level.
- If using Slope Input, enter the slope value for the roof surface. The calculator will compute the corresponding vertical rise.
5. Click “Calculate”
The calculator will process your input and display all calculated roof measurements, including areas, slopes, (some) rafter lengths, and the pitch multiplier.
6. Click “Clear”
Resets the calculator so you can input a new set of values.
Important Notes
- In slope mode, the calculator automatically determines roof height. In height mode, the calculator automatically determines roof slope.
- In USA mode, enter only the first numerical value of the slope (for example, enter
6for a 6-in-12 slope). The calculator accepts decimals for slope values as well. - All inputs must be positive numbers. The calculator accepts decimals for feet or meters, but not fractions or subunits like inches or millimeters. Error messages will appear beneath invalid fields.
- The roof pitch multiplier is used to convert footprint area to roof surface area. It is calculated based on the slope of the roof.
Pyramid Roof Calculator
This tool can help with estimating materials, planning sheathing coverage, or understanding the geometry of your pyramid-style roof. Don’t forget to include any eave overhang in your roof dimension inputs; roofs typically extend farther out than the exterior walls of the building, so you can’t just use the width and length of the walls.
Pyramid Roof Calculator
About the Author
Jack Gray spent 20 years as a principal roof consultant with the Moriarty Corporation, an award-winning building enclosure consultant firm founded in 1967. Mr. Gray has worked in the roofing industry for over 25 years, with training and practical experience in roof installation, roof inspection, roof safety, roof condition assessment, construction estimating, roof design & specification, quality assurance, roof maintenance & repair, and roof asset management. He was awarded the Registered Roof Observer (RRO) professional credential in 2009. He also served as an infantry paratrooper in the 82nd Airborne Division and has a B.A. from Cornell University.