Garage doors are available in a variety of sizes, and one of the first things you will normally be asked when shopping for a new door is whether or not you need a single or a double garage door and what size of door you need. Will you need two single doors, a double door, or a combination of a single and a double for a three-car garage? How many vehicles are you going to park inside the garage, and how big are they? If you are replacing your door, do not assume it is a standard size because there are many exceptions. You will need to measure your existing door to be sure, but here are some standard sizes to give you a basic reference.
For a normal home with a normal car, truck, SUV or van parked inside, a standard residential garage door measures either 8 x 7 feet, 9 x 7 feet or 10 x 7 feet.
Height: Garage door heights are typically seven or eight feet tall. Older houses might have shorter doors because most people just had cars back then and not SUVs and vans with additional racks and carriers attached and oversized trucks with mirrors that extend out.
Width: Eight or nine feet is the most common. On older homes, single doors tend to be eight feet wide, but nowadays, with the oversized vehicles, ten foot wide single doors are getting to be more common. If you need a double door, you would double the width. A double garage door measures out to 12 x 7 feet, 14 x 7 feet and 16 x 7 feet. This is designed for more than one vehicle and for bigger vehicles to fit inside your garage as well. The standard garage doors are sixteen to eighteen feet wide and some are as wide as twenty feet.