Few homeowners would ever want to describe their home as a McMansion, but some of their neighbors who can no longer see the sun may be so inclined. The use of the term McMansion appears to have started in the 1980s, as more and more upper middle class families began seeking larger homes in the suburbs. A McMansion is generally described as an oversized home containing at least 3000 to 5000 square feet (279 to 465 square meters) of living space. A McMansion fills the gap between the smaller "starter homes" and the custom-built mansions found in exclusive neighborhoods.

The allusion to the McDonald's restaurant chain is important to understand when it comes to a McMansion. Much like the hamburger chain's franchises, a McMansion could spring up anywhere at any time. Builders rarely consider factors such as local architectural traditions when contracted to build a McMansion. A 5000 square foot McMansion with numerous gables and boxy additions could appear next to a traditional ranch-style home, creating a noticeable change in the neighborhood skyline.

Improvements in home building designs and techniques encouraged the popularity of McMansions among young professionals with growing families. For relatively the same price as a traditional two bedroom house, potential homeowners could have a spacious two-story McMansion built on a lot far from the dangers of city life. Hundreds of planned communities with idyllic names such as "Pleasant Grove Estates" or "Hickory Hills Place" sprang up all over the United States, each offering lots and other amenities for McMansion buyers.

Proponents of the McMansion phenomenon say the oversized homes feature a number of amenities previously considered unaffordable by middle and upper middle class families. A McMansion is often prewired for advanced sound systems and home theaters. The kitchen space in a typical McMansion contains an abundance of workspace on granite counters, along with the latest appliances and storage concepts. The garage in a typical McMansion can accommodate a two or even three car family, or can be converted into a workshop or recreational room.

Critics of the McMansion craze say the homes often come across as ostentatious and antiseptic. Because their designs are so similar, there is nothing to distinguish one from another architecturally. While the floor plans may call for large, open great rooms or a generous supply of windows, the heating and cooling demands of a McMansion can be considerable. Builders may not orient a McMansion to take advantage of the sun's natural arc, for example. The vast expanses of open space in a typical McMansion cannot be used for any real purpose, such as additional bedrooms or a home office.

Some have called a McMansion the architectural equivalent of the gas-guzzling sports utility vehicle, or SUV. The owner of a McMansion may consider additional utility expenses to be the negligible cost of owning a status symbol. Critics of the McMansion mindset, however, consider the homes to be more ostentatious than practical, with functional rooms rearranged for maximum aesthetic value instead of convenience or practicality.