Build the stud schedule
Count regular studs from the selected layout and add explicit corner, intersection, opening, and backing members.
Separate different wall heights, stud sizes, or grades.
Calculate plates by linear feet
Plate length = wall run × number of plate courses before stock-length optimization.
Splices, laps, openings, treated bottom plates, and stock lengths affect the purchase count.
Take off openings as assemblies
Headers, sills, king studs, jack studs, and cripples depend on opening size and design.
Do not substitute one generic pieces-per-opening factor when drawings provide details.
Calculate sheathing independently
Net sheathing area and sheet coverage provide a first sheet count, but orientation, openings, blocked edges, and cut reuse affect layout.
Round to whole sheets after the layout allowance.
Verify the wall design
Structural loads, shear, bracing, fastening, fire blocking, headers, and connections are outside a simple material count.
Use approved plans and applicable requirements before ordering.