The Groin Vault calculator will return the lofting ordinates to plot the ellipse for different types of groin vaults.

Types of Groin Vaults Supported
 SemiCircular Square Groin Vault
 SemiCircular Rectangular Groin Vault
 Segmental Square Groin Vault
 Segmental Rectangular Groin Vault
 Gothic Square Groin Vault
 Gothic Rectangular Groin Vault
 SemiCircular Hexagon Groin Vault
 Segmental Hexagon Groin Vault
 Gothic Hexagon Groin Vault
 SemiCircular Octagon Groin Vault
 Segmental Octagon Groin Vault
 Gothic Octagon Groin Vault
 SemiCircular Dodecagon Groin Vault
 Segmental Dodecagon Groin Vault
 Gothic Dodecagon Groin Vault
 SemiCircular Hexadecagon Groin Vault
 Segmental Hexadecagon Groin Vault
 Gothic Hexadecagon Groin Vault
 Imperial/English Inch base 12 —— default.. use American standard pitches over 12.
 Metric 300mm base —— 300mm is 11.81102 inches, similar usage to the American framing squares printed in inches.
 Decimal Inch base 10 —— use this option when working with tangents or using the Chappell Master Framing Square multiply the tangent of the angle by 10
 Imperial/English Inch base 12 —— default.. use American standard pitches over 12.
 Metric 300mm base —— 300mm is 11.81102 inches, similar usage to the American framing squares.
 Decimal Inch base 10 —— use this option when working with tangents or using the Chappell Master Framing Square
Input variables
Arch Width # 1
Enter the width of the main arch opening. This groin vault arch is refered to as the Transverse vault arch.
Arch Width # 2
Enter the width of the adjacent arch opening for retangular groin vaults only. Longitudinal vault arch.
This width is not used to calculate the diagonal cross vault ellipse for the square, hexagon, octagon, dodecagon or hexadecagon groin vaults.
Arch Rise
Enter the riseheight of the groin vault arch opening.
Lofting Spacing
Enter the spacing of the ordinates. The default is 6". Using 1" for the ordinate spacing produces better results.
 Length/Dimensions Input Menu Mode
The output mode selection can be completely different from the input mode.
 Length/Dimensions Output Menu Mode
Groin Vaults
See the online help file for more information and drawings for the different types of groin vaults.