"McMansions" and Energy Inefficiency

by Nick Gromicko, CMI®


“McMansion” is a pejorative term used by critics to describe a multi-story house with no clear architectural style, and judged to be pretentious or poorly designed for its neighborhood. Among their major drawbacks, these homes are inherently energy-inefficient. Mcmansions are energy inefficient

Along with the expanding size of American cars, meals, televisions and waistlines, houses have gotten much bigger over the years, as well. The average American home swelled from 983 square feet in 1950 to 1,500 square feet in 1970, and to 2,349 square feet in 2004, according to the National Association of Home Builders. Other countries have seen similar growth.  The Australian government reports that the average size of a new house increased by 40% between 1984 and 2003, going from 162.2 square meters (approximately 1,745 square feet) to 227.6 square meters (approximately 2,450 square feet). And not only are the houses getting larger, but everything inside them is getting bigger, too. Multiple heating, ventilation and air-conditioning systems are becoming commonplace. And two- and three-zone heating systems are becoming a standard feature.

At the extreme end of this progression are the so-called "McMansions" -- also known as “Hummer Houses,” “Garage Mahals” and “starter castles” -- which exploded onto the real estate market during the housing boom of the 1990s. They tempt those with lesser means with the opportunity to live a life of glamorized opulence traditionally limited to the rich and famous. Years of record-low interest rates and aggressive marketing of upscale homes encouraged more people than ever before to stake their claim at a supersized version of the American Dream.

"McMansions" emphasize interior space. Typically, they have a floor area over 4,000 square feet (280 m2), ceilings 9 to 10 feet high, a two-story portico, huge staircases, two or more garages with oversized doors, room-sized walk-in closets, and a family room with a vaulted ceiling. Not uncommon is a front door hall with a chandelier hanging down 16 to 20 feet, an enormous master bedroom, and a spacious kitchen with a center island.

These homes are inherently wasteful, however, as they require a tremendous amount of raw materials to construct and extra energy to keep them running. The "McMansion" thus seems starkly out of place in an era when homeowners are seeking to reduce their energy expenditure and using myriad tactics to meet this goal, from greenscaping and solar gardens, to hiring InterNACHI energy auditors. 

Specifically, "McMansions" pose the following environmental risks:

  • Vast tracts of land must be deforested in order to build unnecessarily large homes, threatening wildlife and reducing the biological absorption of greenhouse gasses. The math is startling: roughly 408 trees of 20-inch diameter and 42 feet of usable wood are required to build an 8,000-square-foot house (according to the Idaho Forest Products Commission), and for every 10 such homes that are built, more than 7 acres of forest must be cleared (assuming 9-foot by 9-foot tree spacing, according to a formula by the University of Georgia).
  • Concrete is required to make foundations, which are correspondingly large in "McMansions." Concrete production consumes energy and contributes to greenhouse gas emissions.
  • Inordinately high energy consumption is another drawback. While they may be grand looking, the high ceilings and huge foyers are difficult to heat and cool. Indoor pools, exercise rooms and living spaces with elevated ceilings all contribute to the need to construct power plants and increase dependency on fossil fuels.
  • Toxic building materials, such as some types of paint and vinyl, are used in greater quantities than are required in typical homes. According to the Environmental Protection Agency, vapors or volatile organic compounds in paint can cause serious health problems.
While "McMansion" owners may discover efficient ways to heat and cool their homes by hiring an InterNACHI-certified energy auditor, whole communities have taken actions to limit the potential energy expenditure of these giant homes. 
Consider the following two examples:
  • In Marin County, California, any homeowner with a home of over 4,000 square feet must fill out a green-building checklist. The larger the home, the more it must conform to standards of energy efficiency.
  • In Pitkin County, Colorado, if a new home is larger than 5,000 square feet, the builder must either provide on-site renewable energy (such as wind turbines or solar panels), or pay a $5,000 fee to the Colorado Office of Resource Efficiency, which will use the money for renewable energy projects elsewhere. Such homes’ energy consumption is watched, too, and if it exceeds predetermined limits, the owner must purchase electricity from the Renewable Energy Mitigation Program.
In summary, "McMansions" are exorbitantly large, environmentally unfriendly homes that may be falling out of fashion as homeowners and even whole communities strive for energy efficiency.