Bigger Is Better
Garages are used as workshops, parking spots, laundry rooms and for storing all those things you wish you would have never bought. With so many uses, it's important to allow plenty of space. Two-car garages are typically at least 18 feet wide by 22 feet deep. This allows room for two 9-foot garage doors and for cars to pull in completely.
Of course, if you don't plan on parking a car in your garage, you may opt for a smaller structure. If you feel you do not need a large garage, then a 12-foot-wide by 22-foot-deep unit will suit your needs.
Always plan the size of your garage so that it corresponds with your needs. Consider questions such as, "Do I plan on parking vehicles in my garage?" or "Do I need a workbench in my garage, or will it be used for storage?" If you answer "yes" to any of those questions, go with a two-car garage. The rule of thumb is that bigger is better.