THE STEEL TAPE MEASURE
All point and circumference measurements (except the length of main beam) must be taken with a 1/4-inch flexible steel tape and calculated to the nearest 1/8-inch.
CORRECT PLACEMENT OF STEEL TAPE
When measuring lengths of points with the steel tape measure, always place the hash marks on the tape against the centerline of the point being measured. This will give an exact length measurement over the centerline of the point from its tip to its baseline. If the opposite side of the tape is laid along the centerline of the point, the length will be read 1/4-inch right or left of the centerline, which may be shorter than the true length of the point.
MEASURING MAIN BEAMS WITH A STEEL CABLE
All main-beam measurements must be taken with a 1/16-inch diameter steel cable. All measurements are calculated to the nearest 1/8-inch. The steel cable is a more accurate and convenient way of obtaining the main-beam measurements.
MEASURING TO THE NEAREST 1/8-INCH
All measurements are taken and expressed to the nearest 1/8-inch. Any measurement which lands on a 1/16-inch mark is automatically rounded off to the next highest 1/8-inch. However, if the measurement lands on a 1/32-inch mark, the measurement is rounded off to the next lowest 1/8-inch.