What is the maximum cubic inch capacity of a 1 1/4" deep 4" square metal box?

To determine the maximum cubic inch capacity of a 1 1/4" deep 4" square metal box, it’s important to apply the formula that calculates the volume of an electrical box. The formula for the volume of a box is:

Volume = Length x Width x Height

First, we need to convert all dimensions to a consistent unit; in this case, the dimensions are already compatible since they are all in inches. The 4" square box has dimensions of 4 inches on each side—so the length and width are both 4 inches. The height (depth) is given as 1 1/4".

Now, we can calculate the volume:

1. Calculate the volume of the box:

Volume = 4" (length) x 4" (width) x 1.25" (depth) = 4 x 4 x 1.25 = 20 cubic inches.

However, when dealing with electrical boxes, certain allowances must be made for conductors, devices, and other items that may be placed inside the box. According to data provided in the National Electrical Code (NEC), the maximum allowed cubic capacity for use in calculations is typically specified.

For a standard