A question of DESIGN: When you have a double garage door and it is on the front of your home, the door becomes a major element of your home’s design. By putting 2 doors, you put less emphasis on them, giving more balance between the garage doors and the rest of the house. It is all a question of taste. A question of PRATICALITY: If your 16-foot-wide door cannot open, two cars could be stuck in your garage. It’s almost impossible for the same situation to arise if there are 2 doors. If you live in a place where winters are frigid, opening a double garage door lets more cold air into the garage, quickly dropping the interior temperature. Less cold air enters if you only open a single door. A difference in COST: The price for two single doors comes to practically the same as for a double door. This being said, if you want electric openers on both doors, obviously two openers will cost more than a single one.