Launch Slideshow

A key strategy for reducing energy use was to locate common areas and bedrooms on the south side to take advantage of daylight and warmth. Deep overhangs, louvers, a trellis, and deciduous trees shade the large southwest-facing windows. The louvers horizontal slats are angled to deflect direct summer sun but allow solar penetration in winter, based on a design formula that optimizes their shading performance. The Duratherm custom windows are made of FSC-certified Spanish cedar. Their double-pane glazing has a 70% visible light transmittance, an SHGC of 0.36 and a U-value between 0.29 and 0.26. 800.996.5558. www.durathermwindow.com.

A Passive Solar Home for Green Architects

Chris Hays and Allison Ewing live in a home that demonstrate how sustainable design stands the test of time.

A Passive Solar Home for Green Architects

Chris Hays and Allison Ewing live in a home that demonstrate how sustainable design stands the test of time.

  • Project: Hays-Ewing House, Charlottesville, Va.Size: 2,500 square feetConstruction Cost: Approximately $150 per square footCompleted: March 1999Architect: Hays  Ewing Design Studio, Charlottesville General Contractor: Dubose Craig Carpentry, CharlottesvilleConsultants: Loisos  Ubbelohde, Alameda, Calif. (daylighting); Nelson Byrd Woltz Landscape Architects, Charlottesville (landscape architect)

    http://www.ecobuildingpulse.com/Images/tmp136F%2Etmp_tcm131-406375.jpg

    true

    Project: Hays-Ewing House, Charlottesville, Va.Size: 2,500 square feetConstruction Cost: Approximately $150 per square footCompleted: March 1999Architect: Hays Ewing Design Studio, Charlottesville General Contractor: Dubose Craig Carpentry, CharlottesvilleConsultants: Loisos Ubbelohde, Alameda, Calif. (daylighting); Nelson Byrd Woltz Landscape Architects, Charlottesville (landscape architect)

    600

    Philip Beaurline

    Project: Hays-Ewing House, Charlottesville, Va.
    Size: 2,500 square feet
    Construction Cost: Approximately $150 per square foot
    Completed: March 1999
    Architect: Hays Ewing Design Studio, Charlottesville
    General Contractor: Dubose Craig Carpentry, Charlottesville
    Consultants: Loisos Ubbelohde, Alameda, Calif. (daylighting); Nelson Byrd Woltz Landscape Architects, Charlottesville (landscape architect)

  • The roof and the north, east, and west walls were built with Enercept SIPs, which the firm says save 50% on heating and cooling costs and are two-and-a-half times stronger than conventional framing. The south wall, which is mostly glass, was stick-built. 800.658.3303. www.enercept.com. Parts of the front and side elevations are clad in HardiePanel, a low-maintenance fiber-cement siding from James Hardie with a 30-year warranty against cracking, rotting, hail damage, and termites. The material doesnt expand and contract as much as wood-based sidings, says the maker, and hasnt needed a paint touch-up since it was installed 11 years ago. 888.542.7343. www.jameshardie.com.

    http://www.ecobuildingpulse.com/Images/tmp1370%2Etmp_tcm131-406384.jpg

    true

    The roof and the north, east, and west walls were built with Enercept SIPs, which the firm says save 50% on heating and cooling costs and are two-and-a-half times stronger than conventional framing. The south wall, which is mostly glass, was stick-built. 800.658.3303. www.enercept.com. Parts of the front and side elevations are clad in HardiePanel, a low-maintenance fiber-cement siding from James Hardie with a 30-year warranty against cracking, rotting, hail damage, and termites. The material doesnt expand and contract as much as wood-based sidings, says the maker, and hasnt needed a paint touch-up since it was installed 11 years ago. 888.542.7343. www.jameshardie.com.

    600

    Philip Beaurline

    STRUCTURAL INSULATED PANELS
    The roof and the north, east, and west walls were built with Enercept SIPs, which the firm says save 50% on heating and cooling costs and are two-and-a-half times stronger than conventional framing. The south wall, which is mostly glass, was stick-built. 800.658.3303. http://www.enercept.com/.

    FIBER-CEMENT SIDING
    Parts of the front and side elevations are clad in HardiePanel, a low-maintenance fiber-cement siding from James Hardie with a 30-year warranty against cracking, rotting, hail damage, and termites. The material doesnt expand and contract as much as wood-based sidings, says the maker, and hasnt needed a paint touch-up since it was installed 11 years ago. 888.542.7343. http://www.jameshardie.com/.

  • http://www.ecobuildingpulse.com/Images/0510b_EH_HaysEwiing_Deck_1_tcm131-408337.jpg

    true

    600

    SUSTINABLY HARVESTED WOOD
    Cypress Wood used for the louvers, rainscreen cladding, and 400 square feet of decking was pulled by horses from a Virginia swamp. Heart Pine and DOuglas Fir timber beams and columns were cast-offs from a florring factory in New York. Dimensional framing lumber is FSC-certified. The framing lumber is from Kane Hardwood, a subsidiary of Collins Hardwood. Collins: 800.329.1219. www.collinsco.com.

  • Benjamin Moores Eco Spec paint, formerly Pristine, was used throughout the interior. The 100% acrylic paint contains zero VOCs and has low odor. Also specified was AFM Safecoat sealant, which is SCS-certified for indoor air emissions. Benjamin Moore: 800.672.4686. www.benjaminmoore.com. Circle 312.  AFM Safecoat: 800.239.0321. www.afmsafecoat.com. Plycem panels, used everywhere except in wet areas, provide a thermal mass that absorbs the suns heat during the winter months. The material, distributed by Architectural Products, is made of 72% Portland cement and 20% recycled cellulose fiber from cardboard cartons, plus calcium carbonate and water. It passes the fire-rating requirements of ASTM E136 and is typically installed as a substrate sheathing for walls, floors, and roofs. The 8-foot modules follow the houses structural grid, and were finished with a concrete stain and floor wax to create a warmer color. The feeling underfoot, the architects say, is closer to wood than concrete. 800.243.6677. www.architecturalproducts.com.

    http://www.ecobuildingpulse.com/Images/tmp1372%2Etmp_tcm131-406402.jpg

    true

    Benjamin Moores Eco Spec paint, formerly Pristine, was used throughout the interior. The 100% acrylic paint contains zero VOCs and has low odor. Also specified was AFM Safecoat sealant, which is SCS-certified for indoor air emissions. Benjamin Moore: 800.672.4686. www.benjaminmoore.com. Circle 312. AFM Safecoat: 800.239.0321. www.afmsafecoat.com. Plycem panels, used everywhere except in wet areas, provide a thermal mass that absorbs the suns heat during the winter months. The material, distributed by Architectural Products, is made of 72% Portland cement and 20% recycled cellulose fiber from cardboard cartons, plus calcium carbonate and water. It passes the fire-rating requirements of ASTM E136 and is typically installed as a substrate sheathing for walls, floors, and roofs. The 8-foot modules follow the houses structural grid, and were finished with a concrete stain and floor wax to create a warmer color. The feeling underfoot, the architects say, is closer to wood than concrete. 800.243.6677. www.architecturalproducts.com.

    600

    Prakash Patel

    PAINTS AND STAINS
    Benjamin Moores Eco Spec paint, formerly Pristine, was used throughout the interior. The 100% acrylic paint contains zero VOCs and has low odor. Also specified was AFM Safecoat sealant, which is SCS-certified for indoor air emissions. Benjamin Moore: 800.672.4686. www.benjaminmoore.com. AFM Safecoat: 800.239.0321. www.afmsafecoat.com.

     FIBER-CEMENT FLOORING
    Plycem panels, used everywhere except in wet areas, provide a thermal mass that absorbs the suns heat during the winter months. The material, distributed by Architectural Products, is made of 72% Portland cement and 20% recycled cellulose fiber from cardboard cartons, plus calcium carbonate and water. It passes the fire-rating requirements of ASTM E136 and is typically installed as a substrate sheathing for walls, floors, and roofs. The 8-foot modules follow the houses structural grid, and were finished with a concrete stain and floor wax to create a warmer color. The feeling underfoot, the architects say, is closer to wood than concrete. 800.243.6677. www.architecturalproducts.com.

  • Water shed from the roof is collected and filtered in an iris rill and wetland garden to keep it from entering city storm sewers and the Rivanna River, part of the Chesapeake Bay watershed, that borders the property.

    http://www.ecobuildingpulse.com/Images/tmp1373%2Etmp_tcm131-406403.jpg

    true

    Water shed from the roof is collected and filtered in an iris rill and wetland garden to keep it from entering city storm sewers and the Rivanna River, part of the Chesapeake Bay watershed, that borders the property.

    600

    Philip Beaurline

    STORMWATER COLLECTION
    Water shed from the roof is collected and filtered in an iris rill and wetland garden to keep it from entering city storm sewers and the Rivanna River, part of the Chesapeake Bay watershed, that borders the property.

  • A key strategy for reducing energy use was to locate common areas and bedrooms on the south side to take advantage of daylight and warmth. Deep overhangs, louvers, a trellis, and deciduous trees shade the large southwest-facing windows. The louvers horizontal slats are angled to deflect direct summer sun but allow solar penetration in winter, based on a design formula that optimizes their shading performance. The Duratherm custom windows are made of FSC-certified Spanish cedar. Their double-pane glazing has a 70% visible light transmittance, an SHGC of 0.36 and a U-value between 0.29 and 0.26. 800.996.5558. www.durathermwindow.com.

    http://www.ecobuildingpulse.com/Images/tmp1371%2Etmp_tcm131-406393.jpg

    true

    A key strategy for reducing energy use was to locate common areas and bedrooms on the south side to take advantage of daylight and warmth. Deep overhangs, louvers, a trellis, and deciduous trees shade the large southwest-facing windows. The louvers horizontal slats are angled to deflect direct summer sun but allow solar penetration in winter, based on a design formula that optimizes their shading performance. The Duratherm custom windows are made of FSC-certified Spanish cedar. Their double-pane glazing has a 70% visible light transmittance, an SHGC of 0.36 and a U-value between 0.29 and 0.26. 800.996.5558. www.durathermwindow.com.

    600

    Prakash Patel

    PASSIVE SOLAR AND DAYLIGHTING
    A key strategy for reducing energy use was to locate common areas and bedrooms on the south side to take advantage of daylight and warmth. Deep overhangs, louvers, a trellis, and deciduous trees shade the large southwest-facing windows. The louvers horizontal slats are angled to deflect direct summer sun but allow solar penetration in winter, based on a design formula that optimizes their shading performance. The Duratherm custom windows are made of FSC-certified Spanish cedar. Their double-pane glazing has a 70% visible light transmittance, an SHGC of 0.36 and a U-value between 0.29 and 0.26. 800.996.5558. www.durathermwindow.com.

When the power went out for hours during Virginia’s massive snowstorms last winter, architects Chris Hays and Allison Ewing didn’t worry too much about the frigid temperatures outside. They were enjoying the southern sunlight pouring through their home’s two-story windows, while the fiber-cement floors soaked up the heat and the SIPs walls and roof wrapped them like a warm blanket. More than a decade after building their own home—an experiment in sustainable, affordable design—the Charlottesville couple experienced in a new way the power of passive solar.

As former partners at William McDonough + Partners in Charlottesville, known for its pioneering environmental designs, Ewing and Hays were at the forefront of the modern green building revolution. And although the movement hadn’t yet hit its stride when they completed this house in 1999, their approach was so sound it still forms the basis of their work today.

Passive solar design features that help heat the home in the winter and keep it cool in the summer are defining strategies, along with a thermally efficient building envelope, material reuse, a focus on indoor air quality, and stormwater mitigation. “Our home would probably be LEED-certified today,” Ewing says. “If we upgraded our HVAC equipment, we’d easily make Silver or even Gold, based on what we’ve been seeing on other projects.”

They’d found their ideal lot—in the established Woolen Mills neighborhood near downtown—and with views that face south. Like a good neighbor, the house aligns with the street grid, which placed it on a roughly east-west axis, allowing the most abundant sunlight to flood the living spaces in back. The building is separated on the ground level—work studio on one side of a cypress entry deck, living spaces on the other. Upstairs, an enclosed bridge connects the master bedroom above the studio with the children’s bedrooms.

The floor plan captures the site’s solar energy by banking all the utility areas—kitchen, three baths, and equipment closets—on the street-facing north side so that the two-story living areas can enjoy the southern exposure. To achieve that tricky balance between natural light and unwanted heat gain in a warm climate, the pair worked with a daylighting consultant and combined 0.36-SHGC double-pane windows with a series of louvered cypress panels that cover the upper part of the large windows.

“Because the back of the house has some western exposure, the deep overhangs weren’t enough, so the louvers and a trellis shading the first level were critical,” Ewing explains. “We didn’t feel it was appropriate to rotate the house true south, because that would have put it at odds with the urban environment.”

Hindsight is 20-20, but their original vision was crystal clear, too. Designed on an 8-foot grid to utilize standard-issue building materials, the house’s low-maintenance efficiencies have proven their staying power. The fiber-cement exterior siding has needed no paint touch-ups in the years since they installed it, and the durable fiber-cement floors store and release heat from the winter sun, as the couple had hoped. Custom windows that go up to the ceiling turned out to be a smart splurge, too, since the high operable windows in the living room and on the second-floor bridge exhaust warm air from below.

For mechanical systems, they chose “state of the shelf” technology—tested products that were becoming mainstream. In addition to a Trane variable-speed, high-efficiency two-stage gas furnace with two zones, they installed a Trane VAV (variable air volume) handler, which provides fresh air cued by carbon dioxide sensors. But while their 12-SEER cooling unit was the gold standard a decade ago, they now spec 18- or 19-SEER products.

Indeed, technology, and its costs, has evolved over the last 11 years. If the couple were designing their home today, they say they would incorporate solar thermal and tankless hot water. The crawlspace would be conditioned, too. “The current thinking is to seal the crawlspace and pass some air through to create warmer floors and a thermal buffer below the house,” Hays says.

Likewise, the cypress deck outside will soon be replaced with Cambia, a lower-maintenance poplar that’s been treated with heat instead of chemicals to resist rot. The architects like it because it looks like ipe and doesn’t have to be stained. “You can’t get certified ipe anymore, which is a signal that it’s been over-harvested,” Ewing says.

Green checklist notwithstanding, she and Hays are quick to point out that the highest goal of a sustainable house isn’t just environmental virtue, but also that the landscape and building have a lively relationship. “The pervasive light and the sense of connection you feel to the outdoors as you move around the house is more than a technical goal; it becomes a spiritual thing,” says Hays. “Every time we’ve been away, we’ve felt how lucky we are to come back to this place to live.”

Cheryl Weber is a freelance writer in Lancaster, Pa.