How to Calculate Weight Per Square Foot

Weight per square foot is a value used in construction to estimate a load of building components or structural parts. The load should not exceed the established maximum level, since it may damage the materials. For example, calculate the weight per square foot load on a wooden desk that measures 1.4 feet by 2.4 feet and holds an object with the mass 10.5 kg.

Instructions

1. Multiply the length by width to calculate the area in square feet. In our example, the area equals 1.4 x 2.4. This equals 3.36 square feet.

2. Divide the mass (in kg) by the area to calculate the load in kg per square foot. In our example, the load equals 3.125 kg per square foot.

3. Divide the mass (in kg) by the factor 0.453592 to compute the mass in pounds. In the example, the mass equals 23.15 lb.

4. Divide the mass by the area to calculate the load in pounds per square foot. In our example, the load equals 6.89 pounds per square foot.

References

• CIA World Fact Book (Appendix G)
• "Weights Of Building Materials, Agricultural," Factsheet, Department of Agricultural and Biological Engineering, The Pennsylvania State University.