In a tandem garage design, multiple cars are parked inside the garage end to end, rather than side by side as they are in a traditional garage design. Tandem designs are much less common than traditional designs, but a tandem garage can help to maximize garage space in situations where a traditional design won't easily fit.
A two-car tandem garage design is typically the same width as a traditional one-car garage. In this design, the first car is parked with its nose to the back wall of the garage, and the second car is parked behind the first.
A three-car tandem design allows for three cars to be parked in a garage the width of a traditional two-car design. One side of the three-car tandem design is a traditional depth, but the other side is deep enough to allow end-to-end parking of two cars as in a two-car tandem design. Larger designs using the same tandem-parking concept may accommodate four cars or more.
Tandem garages are most useful on narrow lots where parking space is at a premium, such as in neighborhoods where town homes, condominiums or apartments are built close together. A tandem garage may increase the value of the property by providing more parking space as compared to a comparable home with a traditional garage design.
Tandem designs also offer an aesthetic advantage for homeowners who don't like the idea of a large garage door being a conspicuous part of the front of the home. The narrower driveway required by a tandem design also allows for less pavement and more landscaping in front of the home.
The most obvious disadvantage of a tandem garage is the inconvenience of having to move the outer car in order to get the inner car out of the garage. Because of this drawback, the value of a property with, for example, a two-car tandem garage may be less than that of a home with a traditional two-car garage. In some places, tandem garage designs may be prohibited by local zoning requirements or building codes.