Features of ENERGY STAR Qualified New Homes

To earn the ENERGY STAR, a home must meet guidelines for energy efficiency set by the U.S. Environmental Protection Agency. These homes are at least 15% more energy efficient than homes built to the 2004 International Residential Code (IRC), and include additional energy-saving features that typically make them 20–30% more efficient than standard homes.

And with homebuyers increasingly interested in green building, energy efficiency is the place to start. That’s because the energy used in homes often comes from the burning of fossil fuels at power plants, which contributes to smog, acid rain, and risks of global warming. So, the less energy used, the less air pollution generated. And the easy way to make sure a new home is energy efficient is to look for the blue ENERGY STAR mark, the government-backed symbol for energy efficiency.

Any home three stories or less can earn the ENERGY STAR label if it has been verified to meet EPA’s guidelines, including: single family, attached, and low-rise multi-family homes; manufactured homes; systems-built homes (e.g., SIP, ICF, or modular construction); log homes, concrete homes; and even existing retrofitted homes.

ENERGY STAR qualified homes can include a variety of ‘tried-and-true’ energy-efficient features that contribute to improved home quality and homeowner comfort, and to lower energy demand and reduced air pollution:

1. Effective Insulation
Properly installed and inspected insulation in floors, walls, and attics ensures even temperatures throughout the house, reduced energy use, and increased comfort.

2. High-Performance Windows
Energy-efficient windows employ advanced technologies, such as protective coatings and improved frames, to help keep heat in during winter and out during summer. These windows also block damaging ultraviolet sunlight that can discolor carpets and furnishings.

3. Tight Construction and Ducts
Sealing holes and cracks in the home’s “envelope” and in heating and cooling duct systems helps reduce drafts, moisture, dust, pollen, and noise. A tightly sealed home improves comfort and indoor air quality while reducing utility and maintenance.

4. Efficient Heating and Cooling Equipment
In addition to using less energy to operate, energy-efficient heating and cooling systems can be quieter, reduce indoor humidity, and improve the overall comfort of the home. When properly installed into a tightly sealed home, this equipment won’t have to work so hard to heat and cool the home.

5. Efficient Products
ENERGY STAR qualified homes may also be equipped with ENERGY STAR qualified products — lighting fixtures, compact fluorescent bulbs, ventilation fans, and appliances, such as refrigerators, dishwashers, and washing machines.

6. Third-Party Verification
With the help of independent Home Energy Raters, ENERGY STAR builder partners choose the most appropriate energy-saving features for their homes. Additionally, raters conduct onsite testing and inspections to verify the energy efficiency measures, as well as insulation, air tightness, and duct sealing details.

Visit ENERGY STAR for more information.

With data monitoring in place, and conversions complete by September 1, 2007, we were excited to monitor our first full year as an all-electric home.  Today we are proud to publish data collected over the last year, and produce what will be the first of many Performance Verification Updates – providing publicly accessible data proving Solar Harvest’s success as a net-zero energy home.  Visit our streaming live energy systems monitor.

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Visit REGREEN to download the manual. Be sure to check out a case study about an Ecofutures’ deep energy retrofit at 1247 Scrub Oak! In 2008, Ecofutures committed to remodel all of our homes following these guidelines.

Topics he’ll cover include:

• How are we moving beyond green building?
• What do small scale and large scale green developments look like in the future?
• What’s the latest with co-housing initiatives?

(Boulder, CO 7/26/2007)

Now in their second summer living in Solar Harvest, Eric Doub and his family continue to appreciate the value of a well-insulated, finely “tuned” home for year-round comfort, with zero annual energy bills. During the winter, airtight construction and superior insulation were recognized as the key features creating the “charge and coast effect” by which the home passively gained, and retained, solar heat during several consecutive cloudy cold-snap days. Now in summer, it is apparent that these features, along with ample south overhangs, are also responsible for the home’s ability to maintain cool indoor temperatures. “We have been amazed at how the house will be 75˚F at 3pm when it is 95˚F outside. Our first summer here it was astonishing in how well the nighttime coolth held through the hot days,” said Eric.

Completed in November, 2005, Solar Harvest is the City of Boulder’s first net-zero energy home and possibly the first in the nation approved under modern code for construction in a cold climate without a fossil fuel- or wood-burning back-up heater or hot water boiler. Outfitted this spring with a variety of web-based monitoring devices, Solar Harvest serves as an educational tool for learning about homebuilding in Colorado. The live energy monitoring website is publicly accessible at: www.ecofuturesbuilding.com/systemsmonitoring.

Fitting its educational identity, Solar Harvest inspired the question this summer of: “How do we cope with cooling homes (as energy efficiently as possible) in a warming global climate?” 2006 set heat records around the world, including in Boulder. While the home was performing adequately with a passive cooling strategy of windows open at night and shut in the morning, it became evident that increasing above-average nighttime temperatures were insufficient for cooling indoor air to a point that the home could maintain comfortable indoor temperatures during the late afternoons and evenings of 95˚-100˚F days. Also, opening and closing windows was increasingly disrupting sleep of family and guests (going into guests’ bedrooms to close east-facing windows and shades at 6 a.m., for example). In response, Eric sought out a cooling strategy that would be as efficient as possible, and would mirror how the house performed in the winter: “[When] the house just hums along, pretty much hands off, and is the most comfortable place we have every lived.”

The solution came in the form of a 220V Coolerado direct/indirect evaporative cooler with ECM motor manufactured in Arvada, Colorado. The variable speed ECM motor means that the blower modulates all the way down to 100 watts of energy usage to circulate 200 cfm of cool, fresh, air – the same amount of circulation at half the energy usage as the ERV – and, the same energy cost as for the Tamarack fan or miscellaneous Vornado fans throughout the home. To ensure that PVs continue to cover these relatively small electric loads, and for the new electric stove and dryer to be installed in August, 2007, Eric will be adding 1.9 kW of PVs to the existing 6.84 kW array in August 2007.

Last year, Solar Harvest came to within 1% of the zero-energy mark on a source energy basis. By eliminating the natural gas demand, increasing PV size, and installing monitoring devices throughout the home, Solar Harvest is expected to exceed the zero-energy mark by a wide margin next year, and the home’s residents will still be living more comfortably than ever before.

Since October 2005, over 2,500 people have toured the home and it was featured in numerous publications, TV and radio programs, including HGTV and Discovery Science Channel (early August 2007). In December 2005, Solar Harvest was rated the most energy efficient home in Colorado, and, in 2006 Eric received many awards including the CRES Sustainable Building Award and Energy Star’s New Millennium Builder of the Year Award.
Eric Doub of Boulder, Colorado has been involved in green building and renovation for over 20 years. His award-winning company, Ecofutures Building Inc., has grown an average of 35% per year for the last 12 years, primarily due to an ongoing dedication to comfort, health, durability and resource efficiency in residential projects.

The home’s contribution of 197 kWh of renewable energy to the grid prevented 1289 lbs of carbon from being produced at Xcel’s power plant. Taking into account the carbon emissions from the 36 therms used for cooking and clothes drying, Solar Harvest missed designation as a net-zero emissions home by a mere 124 lbs of carbon. This difference in can easily be offset by the purchase of RECs; a single purchase of $5.50 through CarbonFund.org will offset 8 times the amount due.

Through the purchase of a very small amount of RECs, Solar Harvest also successfully met the definition of a net-zero-annual source energy home. Alone, the building missed the source-energy mark by 1%. The deficit of kWh causing the home to miss the definition can be attributed to the normal process of learning about how to best manage the home’s energy consumption and production – specifically, in this case, of the 360-gallon outdoor spa heating with electricity, an unintended event at the start of the year, when the solar loop was first being hooked up and started.

Based on the knowledge gained in the home’s first year and the future implementation of accurate monitoring systems, Solar Harvest is expected to meet and exceed the NZEH benchmark by a wide margin in the years to come.

Since construction was completed in November, 2005, on Solar Harvest, the City of Boulder’s first net-zero energy home, Eric Doub and his family have enjoyed living in “simply the most comfortable home we ever have experienced.” The home is now fondly dubbed the first “Better-Than-Net-Zero-Energy” home. Designed by Eric Doub and his wife Catherine Childs and built by Eric’s award winning general contracting firm, Ecofutures Building Inc., Solar Harvest has achieved many milestones in its first year.

Since last October, over 1,300 people have toured the home and as many others viewed virtual tours of the home through Eric’s presentation at this summer’s Solar 2006 Conference. In December, 2005, Energy Star home performance raters recognized Solar Harvest as the most energy efficient home in Colorado, achieving 97.7 out of 100 possible points. And in July, Eric was awarded with the Colorado Renewable Energy Society’s Sustainable Building Award for innovation and energy efficiency in residential construction of Solar Harvest.

Built to achieve net-zero energy means that the home incorporates appliances, systems and controls into a home design, such that over the course of a year the home will consume less energy from the utility grid than it supplies to the utility. In recent study of the home’s energy production, it is apparent that within the first 4 months, the PV array generated enough electricity to offset any it consumed before thermal systems were fully operational. Within another 2 months, the home supplied twice that amount; meaning that while other homes turned up air conditioners and faced rising utility bills for the summer, Eric and his family continued to experience pleasant conditions using less energy than ever before.

Features of the home that create these comfortable, energy efficient attributes include: a super-insulated, tight building envelope; a 6,000 gallon super insulated tank for solar hot water storage; a 6.84 kW PV array; and high efficiency appliances. These unique design features – using commonly available materials and standard building practices – allowed Solar Harvest to possibly be the first home in the nation approved under modern code in a cold climate, without back-up heat systems powered by either fossil fuels or wood.

“Ultimately there are two projects here: One is the house as a sustainably built structure, and the other is the home we create within,” Doub says. “With the solar greenhouse for heating and horticulture, and super-efficient systems for space and water heating, we are creating a living environment that is safe and comfortable, and while relatively large in size, also light on the planet. In a sense we are making the future become the present, sooner. As energy guru Amory Lovins says of the coming transition from fossil fuels to sustainable systems based on efficiency and renewables: Why not enjoy the inevitable?”