Knowing how to measure garage doors is not just useful. It’s necessary. When it comes to garage door replacement, you need to know exactly what size door to order. This is one of your first priorities before you buy a new garage door. Choosing among styles, materials, and designs comes next. If you don’t get the right size door, you’ll be in trouble. And that’s why it’s often recommended that you ask the help of a pro garage door company.

What’s tricky with garage door sizes?

You are most likely familiar with the dilemma: which came first: thesingel door chicken or the egg? Somehow, you might find yourself having a similar dilemma when it comes to buying new garage doors. What you find readily available on the market are standard garage door sizes. And so when you measure the existing door, your estimates will help you choose among the standard double or single garage door sizes. If your garage is larger, you can order custom sizes. What you need to be careful with is your personal needs. If you plan to get a bigger car or buy a van, the current measurements of the single door won’t help if you intend to buy a double door. In this case, you surely need the help of a garage door service pro.


How to measure garage doors

One more thing to keep in mind is that not all residential garage doors are the same. Apart from their size, they differ in the way they open. So the space you’ve got in the garage often determine which garage door type will fit best. With that said, let us consider which parts of the garage you should measure.


  • Knowing the rough opening size is very important. That’s the width andbluegd height of the opening without the frame.
  • You also need to check the side clearance. In other words, you must measure the distance from the opening to the wall on each side. This is vital for overhead door systems, which utilize a track assembly.
  • Measure the headroom. That’s the space between the top of the opening to the ceiling. This is extremely significant too. The space available will indicate which garage door springs you should get too. A torsion spring will require at least 12” space whereas extension springs will required at least 10”. It’s important to remember that rollup garage doors keep their barrel over the opening. And so they need plenty of headroom. If there is limited headroom space, bring the problem to your dealer since there are solutions for narrow spaces too.
  • The backroom is the distance from the opening to the rear wall of the garage. It’s important to know the exact measurement for overhead garage doors which open up all the way inside the garage and stand under the ceiling. Since the height of the opening will equal the height of the door, the backroom should be that plus 18”.

Although up & over garage doors are not very popular, remember that they are very particular. If you like this type, remember to check & measure the space outdoors. You need to have enough room for the door to open outwards before it moves up.


Getting accurate measurements and crisscrossing them with your garage door needs is of the essence. If you are not sure you can measure with precision, ask help. A garage door repair company will be able to send you a pro that will measure right and help you decide on garage door sizes based on your needs.