Setting out
Courses within a target height
- where
- whole courses
- target height (mm)
- gauge = unit height + bed joint (mm)
- remainder (mm)
Explain this equation
This tells you how many whole courses fit within a target height and how much is left over. Use it when working to a fixed height such as a sill, a lintel or a floor level.
H is the target height in mm. g is the gauge, which is the unit height plus one bed joint. n is the number of whole courses that fit, and r is the leftover height that is less than one course. The calculator also shows the height of n + 1 courses, the next full course above the target.
Dividing the target by the gauge gives the number of courses, and the ⌊ ⌋ brackets mean round down, because only complete courses fit. Whatever height those whole courses do not use is the remainder, H − n × g.
With a 75 mm gauge, 2450 mm holds 32 courses (2400 mm) with 50 mm left over; 33 courses would reach 2475 mm.
Watch out: do not simply spread the remainder across the joints. Check the permitted joint tolerances and the design first.
Find whole course modules and the residual height.
Enter your values to see the result.
Good to know
Do not spread the remainder into joints without checking permitted joint tolerances and the design. Includes one bed per course.
Sources
- BDA dimensions
Estimates are not design approval or British Standards compliance checks. Structural arch, retaining-wall, wind, foundation, lintel and masonry-capacity design are not performed. Use the project engineer’s specification.