Camber Arch Calculator

Calculates brick sizes at the extrados and intrados for a flat camber arch using: 60° skewbacks, max extrados brick 65mm, key brick centred. Intrados taper list is produced when rise ≥ 1%.

Inputs

Span at springing line (intrados) — mm Depth of Face (excluding lower bed joint if present) — mm

Perpendicular joint — mm (1–10)

Intrados rise — % of span

Method used:
• Skewbacks fixed at 60°.
• Extrados length is calculated from span, depth, and rise.
• Courses are chosen as the smallest odd number that gives an extrados brick ≤ 65mm (as close to 65 as possible).
• For rise ≥ 1% the intrados is a circular arc with the specified rise at midspan, and joints radiate to the striking point (equilateral triangle from span). Intrados brick widths are measured along the intrados arc between joint centre-lines, minus the constant joint size.

Results

Extrados length

—

Courses (bricks)

—

odd number (key centred)

Perp joints

—

= courses + 1

Extrados brick size (each)

—

mm (≤ 65)

Intrados rise

—

Intrados note

—

Item	Value	Units / Notes

Skewbacks: fixed at 60°. Max extrados brick: 65mm. Units: mm.