The standard length, or depth, of a garage ranges from 20 to 28 feet or longer. The standard width ranges from 14 to 30 feet. The actual finished length depends on the required amount of extra storage or work space, vehicle sizes and walking room.
The minimum garage length for an average-size car is 14 feet, while the minimum length for a full-size pickup truck, van or SUV is 22 feet. To incorporate a work space or extra storage at the back of the garage, add 4 to 10 feet to the minimum length. To ensure comfortable movement on all sides of the vehicles, add 2 to 4 feet to the length and width of the garage.