Like windows and doors, installing a garage door begins
with framing. Appropriate header and trimmer studs are needed to support the span of the
garage door opening.
A typical single garage door is 8'or 9' wide by 7'
high. The rough opening should be about 1 1/2" bigger on each side than the door to
accommodate the jambs.
Top, side and back jambs finish the rough opening.
Install the header jamb first. In some cases this takes two 2x6s or larger lumber. To span
the length of the opening, the two header jamb pieces can be mitred together,
instead of butted.
NOTE: Housewrapping between the jambs
prevents air infiltration.
Screw side jambs to the trimmers for the correct
opening width. Install back jambs flush with the corner side jambs. The door brackets will
mount to the back jambs, so make sure they are square.
The top plate above the garage door header may take
two sections. So splice them at a cripple stud above the header or above a wall stud.
Cap the top plates with 2x4s to add strength and
stability.
