How To Measure Garage Door Height. Then, measure the height by running your tape measure along your door. First measure the height and width of the garage door.
Measure from the floor up to header in three spots; The height of your car makes a difference. Measure the backroom, the distance from the garage door opening to the back wall of the garage.
This is the distance between the right and left sides of the finished opening.
Step #1 measure the width and height (1 and 2) of your door opening in feet and inches to determine the garage door size you need. To measure the height of your garage door, measure from the ground where the garage door rests to the horizontal jam board at the top of the opening. Make sure to check if your garage door has any strips attached to the bottom that will account for extra height. Use a step ladder to more easily measure the ceiling height.