Should You Build a New “Green” Home, or Retrofit Your Current Home?

Philip S. Wenz

When we think of a “green” home, we usually get a picture of a shining new edifice made from straw bales, adobe or experimental materials, complete with solar electric panels and a high-tech heating system. Perhaps the building has an unusual shape, resembling a dome or a crystal, or is built underground. To many, the ideal eco house is just a bit out of the city, away from civilization’s annoyances but replete with every modern convenience. It all sounds great, until we contemplate the price — and the cost to the environment. If affordability and being really green, as opposed to trendy green, are considerations, I’ll argue that no matter how environmentally correct its architecture, building a new house, especially in a remote location, will always have a greater negative impact on your budget and the environment than retrofitting an existing home.

It’s obvious why a custom, high-tech home on an ideal lot would be expensive. Less often discussed are the detrimental effects of land use and infrastructure — usurped farm land or forest, felled trees, rerouted drainage, roads, wires, pipes, wells and septic systems — required for the new structure.

Also, if your house is out of town you’ll have to commute, at least for supplies and probably to work. Unless you plan to walk or ride a bicycle, which becomes less practical as the distance increases, choosing to commute, even in the most fuel-efficient vehicle, is choosing to impose an extra burden on the environment.

Added to the location and infrastructure issues is the simple fact that new homes have a lot more "embodied energy"—the total amount of energy and materials required to create them—than retrofitted existing homes. Even if an existing home needs to grow to accommodate an expanding family, adding a couple bedrooms is far less taxing on the environment, and your pocketbook, than building a house from scratch. And although it can be a little messy, adding insulation, solar panels, gray water systems and other eco-friendly features to a house is straightforward, and can be done in affordable stages.

Another consideration is the demographics of existing and new housing. According to a U.S. government housing survey, there are roughly 120 million single-family dwellings and duplexes in the country. About 1.35 million new units, or 1.1 percent of the existing homes, are added each year. If those numbers hold steady, almost 90 percent of the houses that will exist in 10 years already exist today.

Most climate scientists think we have a 10-to-15 year window of opportunity to start slowing down the global warming trend, and reducing the energy used in buildings is a big part of that equation. Obviously, new buildings should conform to rigid energy-use standards, and ideally they would be net energy producers equipped with solar panels that can feed electricity back into the power grid. However, if we don’t do something to ensure that our existing housing stock is energy efficient, and again, ideally, energy productive, any gains made from regulating new housing will be nullified or reversed.

As a society, we need to decide whether we’re going to get serious about global warming and other environmental problems before it’s too late. While some of those decisions will be made by politicians, individual homeowners, added together, can have just as much influence on the outcome of environmental megatrends as governments. Giving careful consideration to housing (and transportation) choices is an essential component of a new environmental strategy.

None of this means that you have to feel guilty about building a new home if your heart is set on it. But if you do opt for new construction, and you want to live lightly on the earth, think carefully about what will make your home truly green. Consider "infill development," that is, building between houses in an existing community, and, therefore, tying into existing infrastructure. Keep your scale small — and your green ideas big — so you can show others what’s possible.

But if you want to keep the effect of your need for housing to an absolute minimum, stay where you are. There is no reason why, with a little thought and work, your house can’t become your ecological house.