How this calculator works
The calculator divides wall length by stud spacing and adds one end stud. It then adds two extra studs for each opening as a rough allowance. Plate lumber is estimated as three runs of wall length for a bottom plate and double top plate. Stud linear feet include waste, then convert to 8-foot board count.
Example: a 24 ft wall at 16 in spacing has 19 base stud positions. With two openings, the estimate becomes 23 studs. Three plate runs require 72 linear feet of plate lumber.