8/22/2011 - The green house next door
by J Rottet - Newsandobserver.com
A GREAT article, answering some common questions regarding where and how you can build a "green" home ANYWHERE! It doesn't have to be funky or eclectic - sustainability and green construction can take the shape of anything you want - and it does here in Wetern North Carolina, as it does in Raleigh and other parts of our beautiful corner of the country.
Built by NCGreenBuild, the home is a textbook example of green construction - designed to be stingy on energy and water use and provide clean air indoors. Outdoors, drought-tolerant landscaping needs little water and will help keep runoff out of the city's stormwater system.
Steve Frasher, co-owner and manager of NCGreenBuild, talked with features editor Carole Tanzer Miller about the energy-saving aspects of the home, which recently received the U.S. Green Building Council's LEED certification. This is an edited transcript.
Q: What makes a "green home"?
A lot of people are aware that "green" encompasses using environmentally friendly materials that have less of an impact on the planet (such as recycled products) or building more energy-efficient structures. Other building elements that green building focuses on result in houses that are more durable and easier to maintain, and built with designs and materials that result in a healthier atmosphere for their occupants.
Q: What special hoops are involved in building a green house?
For the LEED program, you register your project with the U.S. Green Building Council. Builders then work with a local LEED provider. We worked with Southern Energy Management, which performed field inspections and performance testing to verify we followed standards required to receive our certification.
Q: Is it more difficult to build green in a subdivision governed by a homeowners' association, or in a historic district where someone might want to retrofit?
Many green projects deal with passive solar design. Additionally, lots of the early adapters of green building design homes with a more modern look. We feel we can build a LEED-certified house that would look perfectly in place in any neighborhood.
One of the biggest things we have learned is that intense planning and design at the beginning are key to keeping green building affordable. When we start from scratch, we can control a lot (depth of exterior walls for insulation, efficient water fixture location, duct work, exhaust locations, etc.). If a structure already exists, you need to spend more money to overcome design issues.
Q: What prompted you to seek LEED certification?
Both Duncan Lundy (co-owner of NC Green Build) and I really see the value of building houses to the standards that the LEED program demands.
We believe that energy efficiency and improved building standards will become more stringent over the next several years. As technology and common practices to measure these attributes become more widely used, we could see in the near future that it may become common when selling a house to do some sort of energy testing at a home inspection (such as infrared cameras to detect poor insulation and tests to see how much air leaks through exterior walls). Purchasing or building a LEED-certified house means your house will meet those increased standards.
There is current confusion in what different "Green Building" labels mean. The development of LEED began in 1993 and is one of the longest standing and proven systems available.
Q: What does it mean and how difficult was it to obtain?
LEED stands for Leadership in Energy and Environmental Design. It is an internationally recognized certification system, providing third-party verification that a building was designed and built using strategies aimed at improving energy saving s, water efficiency, emissions reduction, improved indoor environmental quality and stewardship of resources.
LEED is concerned with several key areas of building and design. Among the most important to homeowners are design, durability, energy efficiency and healthy indoor environment. While the verification, documentation, and intense planning for a LEED built house do make getting the certification more challenging than building a noncertified house, these "hurdles" are why we see the LEED program as one of the best.
Q: How much does LEED construction add to the cost and what savings can homeowners expect down the line?
For this project we needed to compete (on sales price) with the traditionally built homes in the neighborhood. We designed this house to maximize the energy efficiency while still keeping the cost down. We calculate it will end up with around a 6 percent increase in the overall cost to build. This cost obviously increases based on additional features a homeowner would want or by expanding the building specs to achieve a higher level of certification.
Our house received a Home Energy Rating Score based on our building specifications. Our project was rated 45 percent more energy efficient than a home built only to the current energy code.
For details, see bit.ly/r5GiZ4.
To keep dust and debris out of ductwork, HVAC vents are sealed during and after construction. For better indoor air quality, builders use low-VOC paints and adhesives. VOC stands for volatile organic compounds that are emitted by thousands of products, many of them used in construction. The chemicals may be dangerous to your health.
Framing with 2- by
Framing with 2- by 6-inch studs accommodates more insulation than standard 2- by 4-inch construction. This home's pink insulation has a value of R-19, compared to the yellow R-13 insulation (left) used in standard construction. The higher the R-value, the better the thermal performance of the insulation. Fewer exterior studs also mean fewer insulation voids.
Green features include energy-efficient windows, WaterSense plumbing fixtures, EnergyStar lighting and a high-efficiency HVAC system. A fan in the garage removes unwanted fumes from equipment, cars or chemicals stored there. The house is also constructed to be solar ready, allowing the owner to install a solar water heater or solar panels if desired.
A catch basin is
A catch basin is designed to minimize runoff that can overburden urban storm drains. Rainwater runs off the roof and driveway, collects in the basin and seeps slowly into the earth, minimizing erosion and reducing the burden on stormwater infrastructure. A row of cattails provides a pretty view.
Water-resistant exterior sheathing protects against moisture and is energy efficient. Combined with extra, advanced air-sealing insulation, it helps provide a strong barrier against heat and air loss. On a scale established by the Residential Energy Services Network, a typical new home rates 100. This home rates 55, meaning it is projected to be 45 percent more energy efficient.
To prevent infiltration of cold air in winter and hot air in summer, all cracks are hand-sealed with caulk. The house has a fresh-air intake in the HVAC design. Exhaust fans and venting are designed to meet LEED and Energy Star requirements.
A radiant barrier
A radiant barrier installed under the roof helps reflect the sun's he at, minimizing its effect on indoor temperatures.
Pre-cut framing components help reduce construction debris. Construction waste is recycled whenever possible.
The crawl space
The crawl space will be sealed and insulated for more efficient heating and cooling. Sealing and insulation will also help prevent damaging mildew and condensation.
Learn more about LEED, the Leadership in Energy and Environmental Design Green Building Rating System of the U.S. Green Building Council at tinyurl.com/ax9px.
Federal agencies offer tips on saving energy around your home, as well as rebates, tax credits and financing for energy-efficient products. Visit the U.S. Department of Energy at tinyurl.com/27y28zh Visit the U.S. Environmental Protection Agency at tinyurl.com/chzrmm.
Local utility companies may offer rebates for installation of energy-efficient products, including windows and HVAC systems. Check their websites for information.