Garage Door Opening Requirements

As you may have heard in Matthew 7 a wise man builds his house on rock where a foolish man builds his house on sand.  The equivalent solid foundation for a garage door that looks good, seals well and functions trouble free for years to come is making sure the garage door opening and surroundings comply with certain minimum requirements we will discuss below.

These are the standard requirements that Superior Overhead Door needs to install our garage doors on a residential house with traditional wood framing:

Opening: The size of the finished opening, after trim has been applied, should be same size as door. So if you want a 16×7 door, then your finished opening should be 16 feet wide by 7 feet tall.

Stem Walls:  The stem walls need to be poured 3” wider than the opening. This leaves room for the garage door track railing which will sit inside a 2” jamb (1 ½”).

Floor Inset:  The concrete floor insets need to be wide enough for the track and deep enough for the door to sit inside without touching, as wide as stem walls and min. 3 inches from the wall. Remember to calculate the opening distance from the header to the bottom of the inset which will be lower than the surrounding garage door floor by how deep the inset is poured.  

Side room:  On the side of the doors we need 3 ½” minimum solid wood on both sides of the opening running up the wall 12” above the opening to attach the track. Two 2×4 studs on the edge of the stem walls and jamb makes a 4 ½” solid side for us to secure the tracks.  This construction is standard for new construction. We do come across situations where a single 2×4 on an 8’ wide door inside jamb (only 3 inches) which is insufficient to provide the secure attachment point needed.

Top jamb:  The rough opening of the top jamb needs to be 1 ½” higher than the finish opening so that when the jamb is added it will bring the opening down to finish height. (Lower openings affect the aesthetics of the door).

Header and head room: The head room is the area immediately above the door opening.  For a standard installation a minimum of 12 inches of head room is required to install a door if no garage door operator will be installed.  If you think a garage door opener motor may be installed now or in the future, then you want a minimum of 16 inches.   The header above the door needs to be solid wood for attaching the spring pad and a motor rail if an opener will ever be installed.  

If the header is at the top of the opening with framing then immediately above the door the center needs to be filled in with extra studs for attaching the spring pad (need at least 3” of solid wood). The spring pad takes the weight of the door and the torque from the springs and must be solid. Head room is the area needed for the horizontal portion of the tracks and the where the garage door will be in the up position.  Head room is measured from lowest point from the front wall where the garage door opening is located toward the back of the room where the tracks will be (back room discussed next).  Make sure any beams, lofts, side wall insets or other features will not be in the way of the tracks or operation of the garage door when it is installed.

Back room:  How far back from the garage opening will the door and tracks extend is considered the back room needed to install the door and tracks.  The minimum room needed is the door height plus 8 inches for tracks and other components to fit.

Flat plane: The inside face of the wall next to the door opening needs to be on a flat plane.  The side walls from the top of the opening to the bottom of the door opening need to sit flush in opening to obtain the proper distance and angle for the tracks to allow the door to operate smoothly.

Entry doors: Although the head room and back room requirements already mentioned this, it may be a helpful reminder that entry doors when opened need the top of the door to be lower than the garage door track as well as any cabinets, shelves or other features that may interfere with door or fixture operation.

Lights, fans and attic stairs: They too need to be located outside the door travel area.

Operator wiring:  If you are wiring the garage for a garage door motor you should consider the placement of the electrical receptacle and the operating wiring needed for the wall button to open the door and the safety eyes.  If the wiring is not in the correct location you will have excess wires showing across your ceiling and the plugin from the motor might not reach the electrical receptacle.   On a seven foot tall garage door, once you install the railing and a liftmaster traditional opener, the back of the motor should sit 10 feet, 2 inches away from the door opening.  The receptacle and the wiring for the photo eyes and wall button should is preferably 11 feet from the opening.  Most operator railings are installed in the center of the door opening from left to right.  Sometimes the framing or other considerations require the rail and motor to be offset from center to one side or the other.  If the railing will be mounted offset to one side, then the wiring should also be offset to the same side as the railing and the motor for a traditional operator.  Side mount operators are mounted on the shaft at the top of the railing on either side of the door opening, just above the jam.  If you are using a side mounted motor, then the wiring should be more than 12” from the side of the door opener to give room to mount the opener on the wall.  The receptacle plugin can be in the ceiling above the side mount motor or to the side of the motor as long as it is more than 12” from the opening. (you don’t want the motor mounted on top of the wiring).  Remember the electrical receptacle must be close enough the 6’ cord from the motor (coming out of the top of the motor) can reach the plugin.

The above are standard requirements that we at Superior Overhead Door need to install your garage door successfully.  If you are using another company, they may have other requirements for different brands of doors.  If your garage door area does not meet the above standard requirements, then we can inspect your location and may be able to come up with a custom solution.  As an example, if you do not have the minimum required standard head room, we can buy low headroom hardware to work down to a minimum of 4 ½ inches with no motor.  This low headroom hardware is more expensive than the standard hardware and requires more time and expertise to install, but if that is what you have to work with, then we can help.  Call us to look at your specific situation and let us suggest options that might work for you.