How to measure the opening and surrounding conditions in preparation of a new garage door.

While the actual finished opening will determine the
size of the overhead garage door the surrounding
conditions will determine the track configuration

  The size of the finished opening should be the exact same size as the sectional garage door or down to 1” smaller on each side and/or the top. While technically the door could overlap the opening as much as the space will allow, the design on the outside of the door disappearing behind the jamb will tend to distract from the overall outside appearance. Furthermore if the opening is larger than the door the door may not seal properly against the elements and may also distract the overall appearance.

  Although it is not necessary to measure the opening before requesting a garage door estimate the drawing below (Diagram A) shows the important measurements for the installation of your new overhead sectional garage door.



Distance in-between the two jambs on the outside of the opening



Distance from the floor to the bottom of the header



Distance from bottom of header up to the nearest obstruction (Re: pipes or air vents) or ceiling. 12” min required for standard lift track

Left Sideroom


Distance from the left jamb to the nearest obstruction or wall to the left. 3-1/2” min required

Right Sideroom


Distance from the right jamb to the nearest obstruction or wall to the right. 3-1/2” min required

Backroom - Door


Door height plus 1’0

Backroom - Door Opener


Door opener requires approx 12’2” for doors up to 7’6 tall & increases as door gets taller


Garage Door Opening Diagram A



NetObjects Fusion 2013

Royalty Free Images 

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Ft Myers, FL




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