A Guide to Garage Door Sizes

Garage door
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As house sizes increased steadily through the latter decades of the twentieth century, so did the garages that accompanied them. Not only did the size of one- and two-car garages grow to accommodate the heftier vehicles they had to house, but the number of bays in garages increased from one to two to three, and even more. It reached a point where the typical garage in a new housing development had the same square footage as the typical new house of a few years earlier.

All of this makes for some interesting proselytizing and analysis about our super-sizing culture, but that is not the intention of this article. Here we are more interested in looking at the kinds of problems and decisions this changing face of the garage poses for today's homeowners.

In the Beginning

The first car garage may have been created somewhat accidentally. Legend has it that Henry Ford built his first "horseless carriage" in a neighbor's coal shed in Detroit in 1896. As often seems to happen in these circumstances, once he'd built the thing he discovered that it was too big to get through the door of the shed. Ford improvised; he knocked out enough of the brick wall to let his new creation pass through.

Not too many years later, horseless carriages were being cranked out in volumes on assembly lines. And not long after that, tiny (by today's standards) garages were being built to store and secure the new automobiles. Domestic vehicles have long since outgrown those garages. When you see one now, sitting near an old home, they look quaint, but they also generally see only bicycles and motorcycles rolling through their openings.

Standard Garage Door Sizes

You might be surprised at the range of standard sizes that exist today for garage doors. Leading garage door manufacturers typically sell doors in widths ranging from 8 feet to 20 feet. Smaller sizes can be found; for example, in areas where golf cart transportation is popular, garage doors are usually available to suit these small vehicles.

Those 8-foot-wide doors are not being installed in many new houses these days, but there are still plenty of older homes with garages built to house smaller cars. Replacement garage doors are readily available for these homes.

Standard heights of garage doors are more limited. Usually, they are offered in heights of 7 ft. or 8 ft.

Planning for a New Garage

If you are having a new garage built, there's a good chance that the builder will suggest 9-ft. wide by 7-ft. high doors (assuming you are planning one door for each vehicle in the garage). That's a good size for most of us, but what if you happen to have a large truck, with large mirrors projecting from the sides or a snowplow on the front. Many such trucks have lost those mirrors trying to squeeze into a 9-ft. wide opening. In this case, you might want to give serious thought to going with 10-ft. wide doors, and perhaps increasing the height to 8 ft.

Another big decision to make when planning a new garage is whether or not to have it attached to the house. Though attached garages are the norm these days, there are several benefits to a detached garage. Particularly if you are accommodating unusually large vehicles, a detached garage may provide more latitude in design.

How To Measure for Garage Doors

If you are replacing a garage door, the easiest way to determine the size you need is to measure the existing door. If you happen to have a doorless garage, you will need to carefully measure the width and height of the opening. You will also need to check the clearance above the opening to ensure that there is sufficient room for the garage tracks to be installed.

This is assuming that you plan to buy and install the garage door yourself. If you are going to let a professional handle the job, let him determine the exact size of door you need.

Changing the Size of a Garage Door Opening

From a structural standpoint, it is easy to reduce the size of the opening in a garage, thus creating the need for a smaller garage door. Unfortunately, few people have any need to do this. Instead, it is much more common for homeowners to need a larger garage opening, primarily because their larger vehicles just don't fit well through the existing opening.

Enlarging a garage door opening is often nearly impossible without substantially increasing the size of the garage. The biggest obstacle is usually the headroom above the existing opening. The span above the opening is framed with a long header that will have to be raised (or more often rebuilt). If there isn't enough room above the opening, this can't be done without raising the roof of the garage. That's a big, but doable, job. You also need to consider allowing room for the garage door opener.

You also need to account for the depth and width of the garage after the opening has been enlarged. Just because you can get your bigger vehicle through the doors does not mean you've improved the garage. In fact, you may now have too little room on the sides and in front of the parked vehicle to move, much less to use for storage.

Eliminating the Garage Door (and the Garage Itself)

Sometimes the only way to make room for big vehicles in small garages is to retire the old garage and build a new one. With good design and careful construction, this can be a great improvement to the value and functionality of your home. You can begin by removing the old garage door and planning to convert the old garage to living space.