The Interface Angle from Rise over Run calculator computes the outer angle made by two intersecting right triangles defined by their pitch defined as rise over run.
INSTRUCTIONS: Enter the following:
- (RS1) Rise in Pitch 1
- (RN1) Run in Pitch 1
- (RS2) Rise in Pitch 2
- (RN2) Run in Pitch 2
Interface Angle (B): The calculator returns the angle in degrees. However, this can be automatically converted to compatible units via the pull-down menu.
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The Math / Science
The formula for the exterior angle of intersection of two right triangles is:
B = π + P1 - P2
where:
- B = Interface Angle
- P1 = Angle 1
- P2 = Angle 2
Note: P1 and P2 are two pitches. They are converted to radian angles.
- Pitch to Slope: This converts pitch (e.g., 4/12) to slope.
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- Pitch to Angle: This converts pitch (e.g., 10/12) to an angle in degrees.
- Rise over Run to Angle: This converts rise over run to an angle in degrees.
- Gambrel Angle: Computes the bend at the intersection of two slope as in a gambrel roof.
- Interface Angle: This computes the interface angle between two sloped surfaces.
- Interface Angle from Rise over Run: This computes the interface angle based on two rises and runs.
- Trusses Needed for a Roof: This computes the number of trusses needed for a roof based on the ridge length and truss spacing
- Roof Section Area:
This computes the surface area of an irregular shaped section of a roof.
- Gable Roof Geometries: This computes the lengths and measurements for a gabled roof based on the ridge length, pitch, span and overhang.
- Dormer Geometries: This computes the measurements for a gable dormer based on the dimension of the dormer and main roof..
- Hip Roof Geometries: This the metrics associated with a hip roof based on the dimensions.
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- Double Hip Roof Geometries: This compute the lengths of the dimensional lines where one hip roof intersects another such as in a dormer.
- Pyramid Hip Roof Geometries: This computes the lengths and dimensional lines of a pyramid roof.
- Gambrel Pitch Angles: This computes the pitch angles and rafter lengths in a gambrel roof bases on the span, total height, and height and width of the loft.
- Gambrel Rafter Lengths. This computes the upper and lower rafter lengths, attic width and total height under a gambrel roof based on the upper and lower pitch, span and loft height.
- Rafter Length: This computes the length of the rafters based on the span, pitch and overhang.
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- Corrugation Factor: This computes the material length associated with a structural length using corrugated material.
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Roof Types
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Roofing Calculators