Garage Door Header Span
Their is no notching permitted in the center third of any beam.
Garage door header span. To our knowledge no additional testing has been done to justify continuous headers over multiple garage door openings. Notches on the outer thirds must not exceed 1 6 of the width of the board. Tables providing size selections for various beam spans and loading combinations for southern pine dimension lumber and southern pine glued laminated timber are available for the following applications. Window door garage door headers supporting roof wall floor loads.
Measure the width of your door frame. Most door frames that are 4 feet wide or less require a 2 by 6 header. Both headers and girders are beams that are oriented horizontally and transfer load down to walls piers or posts. Window door garage door headers supporting roof loads only.
When in doubt use 2 by 12 inch headers.