People can debate whether a 10,000- square-foot home, even one built to a high level of performance, could ever qualify as “green.” But for Florida builder Michael Lenahen’s latest project, it’s hard to argue the resource efficiency of its surrounding grounds.
Besides being beautiful and inviting (and interactive, with a vegetable garden and courtyard), the home’s estate-like landscape plan features a wealth of xeriscape features and irrigation systems that promise to reduce maintenance chores and ongoing costs, enhance the home’s performance with shade trees, and—most important—save water. “It continues the sustainable features of the house,” says Lenahen, president of Aurora Custom Homes in Ponte Vedra Beach, Fla. “Saving water is usually far down the list of [a homeowner’s] priorities, if it’s on their radar at all.”
In fact, it was a Certified Green Professionals course offered by Lenahen’s local NAHB chapter that opened his eyes to all things green. “I realized that green building wasn’t just for environmentalists,” he says. “It’s not necessarily new technology or practices, but a consciousness of a systems approach to sustainability.”
Including landscaping. Unless a professional design is required by the developer of the community in which he is building, Lenahen now includes a line item in the construction budget for a landscape architect to steer his clients to native and drought-tolerant plants, low-maintenance layouts and groupings, and water-saving irrigation options. “Consumers are way behind the curve,” he says, more so than they are about energy- and resource-efficient options inside their homes. “There’s a disconnect between the green goals of the house and what can be achieved in the landscaping.”
For the beachfront custom home he finished in June, Lenahen and the landscape architect—working from a basic plan by the owner (who also designed the house) and using the resources of the local Environmental Planning Department—selected native trees and plants that could survive primarily on what the Northeast Florida coastline climate would provide.
In addition, mature shade trees (also native) are used to shield the house from the sun to supplement the benefits of the home’s high-performance thermal envelope. Strategically placed bioswales use drought-tolerant groundcover over a rock-filled French drain to capture and filter rainwater runoff to keep it from the city storm drain.
Besides natural landscape features, the plan also includes an irrigation system that all but eliminates the need for city water. A system of perimeter gutters and downspouts direct rainwater to underground cisterns, which serve a drip irrigation system.Finally, like the bioswales, Lenahen used permeable concrete pavers for the driveway and other hardscape areas to filter stormwater runoff into the ground instead of allowing it to run into the sewer system. “I suggest them for every home because people like their aesthetics and I know their benefits,” he says.
Lenahen realizes that not all builders and homeowners can go to similar extremes. Cisterns, he says, are especially expensive (about $40,000) and carry a long payback, so he recommends wells to serve a similar purpose when the budget is less forgiving. “It’s a one-time fee [to dig and set up a 250-foot well] and it pays back in about two or three years in Florida,” per city water-use rates, he says.
In addition, he suggests managing the irrigation water separately. In his market, for instance, the city does not distinguish between sewer and water use. Irrigation water is therefore grouped in with a home’s total water/sewer bill. An independent irrigation meter that accounts for the well/cistern water offsets the monthly utility bill and pays back in about 18 months, after which irrigation water is essentially free. “It’s like a light bulb going on when you realize what can be saved,” he says. “Why isn’t this going on more?”
