How to Determine Minimum Framing Header Height
- 1). Measure the actual height of the door you want to frame with a steel measuring tape. Sometimes door dimensions are mismarked, so you should always measure. Most doors you frame will be either “six-eight” or “six-ten” doors.
- 2). Install the doorjambs first before installing the header. Doorjambs are the sides of a door frame, and the header is the top of a door frame opening. Each of the two doorjambs is made of two two-by-fours. The outermost two-by-four extends from the door sill, or bottom of the door frame, to the “plate” or top of a framed wall. The inner two-by-four of this pair on each side of the door (the “cripple” stud) extends from the sill to the header, which is the top of the door frame.
- 3). Add 2 inches to the true door size. A “six-eight” door is 80 inches high. Always cut the cripple stud 2 inches longer than the door. For a “six-eight” door, the cripple stud should always be 82 inches long. Nail the door header to the tops of the cripple studs with a framing hammer and nails so the header is always 2 inches higher than the door.
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