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

   A very common question to garage door dealers is “what size should I make the garage door rough opening?”. In most cases the answer would be that you want to make the opening the same size as the door and that is the stock answer you will usually get.

Rough Garage Door Opening

   However the correct answer should be that you want the finished opening to be the same size or slightly smaller than the door, so the rough opening will depend on what you are putting on the sides of the opening and underneath the header. Therefore making the width of the garage door rough opening the same size as the door would be fine if you are going to use a thin layer of stucco, vinyl siding, or 1-by-lumber. However if you are putting bricks, thick river rock stones, marble, or anything else on both sides that is more than 1” thick you will want the rough opening the same size as the door plus twice the thickness of the material and the inner space, backing or mortar that you are applying. For instance, if you have a 16’ door and are using river stones that are approximately 2 to 2-1/2” you will want the rough opening to be roughly (pun intended) 16’6”.


   The height of the rough opening would be the height of the garage door plus the thickness of whatever you are putting underneath the header in addition to the thickness of the mortar etc. It should be obvious that you don’t use twice the thickness for the height since you will not be putting anything on the floor, but you have been reminded just in case this thought escaped you at the moment. However I would think that it would be very seldom that you would want to put something thick and heavy underneath the header and expect it to stay there so the height would probably be the same as the door 99%+ of the time. Once again it should be obvious that if you have an arched opening the height would be the same as the highest point of the arch.

   As I stated earlier you will want the finished opening to be the same size or slightly smaller than the door. This way the door will have a nice tight seal once the weatherseal or door stop molding is applied. If you make it slightly larger than the door the door may not seal completely without using a thicker molding on the outside and the thicker trim pieces may end up looking out of place on an otherwise professional looking installation. When I say slightly smaller I am talking 1” at the most on each side and at the top. If you are using a raised panel door the edges of the panels will disappear behind the wall if you make the opening too small. To me this destroys the whole look of the house and only shows a lack of planning.

   Speaking of disappearing panels and arched openings this also brings up the question of what is the best type of garage door to use. I am not a big fan of seeing panels disappear behind the arches and personally I think it looks rather tacky. If you are using arched openings you could use a flush door but you could give your house a more unique and personal look by using one of the carriage house types of doors. Just make sure you get the measurements of the arch on the door before you do the arches on the house. This way you can make the arches match and then your house will truly look like it was done by a professional.

   As you can see with the proper planning on your garage door rough opening your project can turn out to be one that you can be proud of to show off to your family and friends. Of course if you have any other questions you are always welcome to contact your local garage door dealer and they will gladly assist you on your project from start to finish. This is an up and down business so to speak but if you follow this advice this project will certainly not let you down!!!




NetObjects Fusion 2013

Royalty Free Images 

 If you are a IDA Garage Door Dealer (Members Only) & don’t see your company on our IDA dealer page for your state(s) please contact us and we will make sure to add you during an update.
© 2002-2020 Greg Smith | All Rights Reserved
Site Owned & Maintained By:
Greg Smith
Ft Myers, FL




Garage Door Rough Opening


Garage Doors & Garage Door Openers,
The Best Dealers To Your Door!


We take great pride in this web site. If you should find anything that is not working properly, please contact us with a note of what was not working, along with the type of browser you are using, the version of the browser, and your connection speed. We hope you find our site a worthwhile experience!