In the dry climate of New Mexico, water conservation takes center stage in any discussion of green building. Bill Roth, president of Clear Creek Management Corp., is showing that efficient practices needn’t require special training or special orders.

In his Arroyo San Antonio Condominium, two attached single-level houses in Santa Fe, Roth used off-the-shelf products to make use of the energy- and water-efficient benefits of tankless water heating and radiant floor heating while still abiding by state regulations that prohibit mixing domestic hot water and hot water for radiant heating. The builder installed a Paloma on-demand water heater as well as an off-the-shelf passive heat exchanger, allowing the same boiler to supply hot water both to the houses and to the radiant heat system. Using a tankless system saves the continuous heating costs associated with a traditional tank system, while the heat exchanger avoids the upfront expense of installing two separate boilers.

Finally, Roth installed a D’Mand Systems supplemental pump to reduce the time it takes for hot water to reach the faucet. When the homeowner pushes the unit’s button, the pump circulates ambient-temperature water in the pipes back to the heater and fills the hot water line with hot water, a process that allows hot water to reach the fixture four to five times faster, according to the manufacturer.

The homes also include dual-flush Toto toilets and ultra-low-flow showerheads and sink aerators.

Outside, Roth specified drought-tolerant plants that are irrigated by rain coming off the roof via a perforated pumice wick system. In addition, graywater from the faucets, shower, and washing machine drain into septic tank infiltrators near trees—every time these devices are used, a tree is watered. Some homeowner education is required to ensure chemical-laden soaps and other pollutants aren’t sent down the drain.

Arroyo San Antonio achieved a Silver rating in the Build Green New Mexico program. To see more of this project’s features, visit http://arroyosanantonio.com. —Katy Tomasulo