Learning Center

Obtaining accurate slopes | dual-slope quick reference

6% Maximum Slope
Although a dual slope laser transmitter is capable of a greater degree of slope, the slump or flow tendencies of concrete limit the slope of the pour. To achieve the maximum slope of 6% , it is recommended to use four-inch slump concrete or stiffer.

Parallel Transmitter Axis to Sides of Pour
When pouring a single or dual sloped floors position the transmitter so that both axis are parallel to the sides of the pour (See Fig. 3 and 4 below).

Note: If the transmitter is not parallel the slope will not fall in the proper direction.

Verify Grade Elevations
Calculate what the grade should be at several key points of the pour, such as corners. Use the transmitter and hand-held receiver with grade stick to verify the grade elevation at these points.

How to Calculate Slope Percentage

Divide the “RISE” of the elevation by the length of the slab “RUN” and multiply this total by 100 to determine the slope percentage.

Example: A .5’ (6 inch) RISE divided by a 150 Foot RUN equals .0033 multiplied by 100 equals a 0.33% Slope.