In recent years, The New American Home has been a beacon of innovation with regard to energy and resource efficiency, earning local and national distinction for low energy consumption and the use of sustainable construction materials and methods. The 2007 version pushes the envelope even farther with an impressive yet cost-efficient stormwater management and recycling system and a marketable application of solar and photovoltaic (PV) collectors for electricity.
Many of the components that make up the home's energy- and resource-efficient scheme congregate on the “flat” roof (which is actually sloped slightly to facilitate drainage). Visible only from the mid-rise condos across the street, the components include the air-conditioning compressors, a generator, an array of PV panels, a solar collector for water heating, and a perimeter gutter system (see “Cistern System,” below). “It was a challenge to adapt a ‘green roof' to an efficient residential scale, but we had the smartest people in the room [working on it],” says Dominguez Arlen, who engaged graduate students from the Stormwater Management Academy at nearby Central Florida University, as well as the professionals at the Florida Solar Energy Center and the IBACOS Building America Consortium, as her consultants. “Now that we're over the learning curve, we can provide guidance to other builders.” The results: a 76 percent reduction in cooling energy use (a huge benefit in sunny and humid Orlando), a 73 percent reduction in heating energy use, and a 54 percent reduction in the energy needed for the water heating system compared to a similarly sized house in the same climate zone.
CISTERN SYSTEMThe creative and comprehensive rainwater management, retention, and reuse system devised by graduate students at the Stormwater Management Academy (SWMA) at Central Florida University in Orlando retains 95 percent of the water generated by a 5-inch rainfall. The system uses both gravity and pumps to direct the water to the 7,000-gallon cistern extending 2 feet under the garage slab, where it is used for irrigation. “This is doable for almost any house design and site,” says Martin Wanielista, director of the SWMA program. “The objective is always to contain as much rainfall as is economically possible.”
- CONCEALED GUTTER: Hidden within the top edge of the stucco-clad exterior walls along the perimeter of the flat roof, the gutter system sends rainwater to a series of strategically placed downspouts.
- DOWNSPOUTS: The downspouts pick up rainwater from the cantilevered planters and from the laundry sink, emptying into a bio-retention trough and passive filtering system along the south elevation that slopes to a catch basin under the driveway.
- CATCH BASIN: The catch basin under the driveway uses gravity to feed water runoff into the cistern, along the way running it through a media filter to reduce solid content.
- CISTERN: Built like a crawl space, the 7,000-gallon cistern under the garage slab is of ample size for the balance of retained rainwater and the site's landscape irrigation needs.
- PUMPS: Two sets of pumps, both located in the shallow basement of the main house, pump water from the downspouts through a gross filtration system and out to the cistern, as well as from the cistern to the irrigation systems on the site, including the roof deck planters.
- PLANTERS: In addition to the roof-mounted planters, the cantilevered planters along the south elevation feature a progressive passive drainage scheme that irrigates the planters below through a series of holes along the underside of the planters above.
CONTRASTS AND COMPLEMENTS: At first glance, the front elevations of the garage and the main house are quite a contrast in styles. But a closer look reveals complementary features and materials, namely the combination of lap siding and stucco, the jutting balcony, and exposed timber brackets (“The softer side of contemporary,” says Dominguez Arlen). One hypothetical backstory suggests that a previous owner finished the garage and in-law suite above to live on site while the main house was being built (a common local practice, historically), but sold the entire property before starting the home. The unbuilt portion of the parcel was then developed much later into a contemporary interpretation of the original garage. “This was a chance to create a model for downtown infill detached housing in this market and others,” says architect Binkley. “This project is an example of what we [as a firm] want to do, but need clients to ask for.”