Massachusetts Construction Supervisor License (CSL) Practice Test

What is the minimum required width of a concrete footing in a 2 story single family dwelling with a soil bearing capacity of 2,000 psf?

1. 15 inches

2. 20 inches

3. 12 inches

4. 24 inches

The correct answer is: 12 inches

The minimum required width of a concrete footing is determined by several factors, including the building's load, height, and the soil bearing capacity. For a 2-story single-family dwelling, the general guideline is that the footing width should be at least equal to the total load divided by the soil bearing capacity, ensuring that the load is distributed adequately to prevent settlement or failure. In this case, with a soil bearing capacity of 2,000 pounds per square foot (psf), to determine the footing width, you generally aim for a minimum width of 12 inches for concrete footings. This size ensures that the load from the dwelling is adequately supported without exceeding the soil's capacity. While wider footings are often used for additional safety or to account for larger loads or different soil conditions, the minimum width of 12 inches is acceptable under normal conditions for a 2-story structure in this scenario. Wider options might be plausible for unusual designs, heavy loads, or weak soils, but the minimum requirement in standard practice adheres to the 12-inch guideline in this context.