A rough opening is the framed opening in a wall that will receive a window or door unit. Getting the rough opening right is critical — too small and the unit won't fit, too large and you'll have gaps that compromise structural integrity and insulation.
Standard Rough Opening Sizes
Interior doors: Rough opening = door width + 2" (for jamb and shims), height + 2.5"
Exterior doors: Rough opening = door width + 2.5", height + 2.5" to 3"
Windows: Rough opening = window unit size + 1/2" each side and top for shimming
Up to 4' span: Double 2×6 header (single story, non-load-bearing can use flat 2×4)
4' to 6' span: Double 2×8 header
6' to 8' span: Double 2×10 header
8' to 10' span: Double 2×12 header
Over 10' span: Engineered LVL beam or steel — consult engineer
Load-Bearing vs Non-Load-Bearing
Load-bearing walls carry weight from above (roof, upper floors). They always require properly sized headers. Non-load-bearing (partition) walls can use a flat 2×4 as a header since they don't carry structural loads. When in doubt, assume the wall is load-bearing.
Anatomy of a Rough Opening
King studs: Full-height studs on each side of the opening — nailed to the top and bottom plates
Jack studs (trimmers): Shorter studs nailed to king studs that support the header at the correct height
Header: Horizontal beam above the opening — typically doubled lumber with 1/2" plywood spacer
Cripple studs: Short studs above the header (and below the sill for windows) maintaining 16" OC layout
Sill plate: Horizontal member at the bottom of a window opening
Rough openings figured out?
Build the full proposal in BuildQuotes or invoice the job directly.