The size of the rough opening for double or French doors should be correctly determined in order to easily install the doors and make sure they close and open properly once installed. This also ensures that there will be no gap causing doors to be uneven and other issues.
To correctly determine the size of a rough opening for double or French doors, measure the size of each door. To get the total width, multiply the width of each door by 2 and add 2 inches. So if each door measures 30 inches wide, the width of the rough opening should be 62 inches. For the height of the rough opening, you need to add 2 ½ inches to the height of the door. If your door’s height is 80 inches, then the height of the rough opening should be 82 ½ inches.