A storey rod, also called a gauge rod, is a lath marked out with the course height, which the bricklayer uses as a measuring stick while laying bricks. Stand the rod beside the work and you can see at a glance where the next course has to sit, without measuring afresh each time.
The reverse of the same rod often carries a second scale: the perpend gauge, used to set out the bricks along the length of the wall. The marks are sometimes cut as notches, so the rod can be used by feel as well.
Why it is used
The size of a brick varies by a few millimetres from one to the next. Measure every course separately and those variations accumulate: after twenty courses the brickwork can be centimetres away from the intended height. You only notice when something no longer fits — at the lintel, at the frame, or where the work meets existing brickwork.
Work out the average course height once and mark it on a rod, and the height of every course is fixed in advance. That way the important levels — cill, lintel, soldier course, eaves — land exactly on a bed joint.
Making a storey rod
- Establish the course height — do not measure one brick, but stand ten bricks on edge against each other, measure the total and divide by ten. Add the intended joint thickness (10 to 12 mm is common)
- Choose a straight lath — a softwood lath of about 20 x 45 mm and 2 to 3 metres long is easy to handle
- Mark out the divisions — set out every bed joint from one datum with a sharp pencil, then check that the last mark agrees with the arithmetic
- Mark the fixed levels — put the datum, the top of the cill, the underside of the lintel and the ground level on the same rod
- Label the rod — write the job and the course height on it; using a rod from another job goes wrong sooner or later
Use the same datum for the whole building, so that the walls arrive at the same course on every elevation.
Related terms
- Course height
- Perpend gauge rod
- Perpend gauge
- Datum
- Brickwork
- Bed joint
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