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GBNT, LEEDS, RESNET, HERS… How Do You Spell GREEN?

The National Association of Home Builders (NAHB) defines Green Home Building Guidelines as the process of incorporating environmental considerations into every phase of the home-building process. That means taking into account the design, construction and operation of a home, energy and water efficiency, lot development, resource efficient building design and materials, indoor environmental quality, homeowner maintenance, and the home's overall impact on the environment.

There are several compelling reasons for changing the way the mainstream currently builds and operates homes. Whether by choice or by mandate, many builders already are incorporating elements of green building into their current practices.

• limiting environmental impact through efficient site design and development
• including resource-efficient designs and materials to maximize function while optimizing the use of natural products
• designing energy efficiency to reduce consumption and energy costs
• implementing water conservation measures both indoor and out
• increasing healthy indoor environmental quality
• educating homeowners regarding proper home operation and maintenance
• using paints with low or no volatile organic compounds and alternatives to toxic cleaning substances and lawn and garden chemicals

Incorporating these principles into the home building process provides lower operating costs, increased comfort, improved environmental quality, less maintenance and enhanced durability.

Green Built North Texas (GBNT) is a voluntary partnership of local homebuilders, industry supporters, and sponsors committed to creating awareness and interest in the construction of resource-efficient homes in North Texas. Homes built to the program guidelines help improve site management, water efficiency, indoor air quality, energy efficiency, material usage, and homeowner education.

Since its introduction in 2006, GBNT has quickly grown to include more than 100 members and has developed numerous technical resources and educational seminars in support of its construction guidelines. The program offers recognition to each home built by participating builders in compliance with its construction guidelines. To attain the certification, a builder must meet each and every requirement on the GBNT list of criteria-in other words, it either qualifies or it doesn't-there are no "shades of green" in the initial program.

Membership in GBNT is open to both builder and associate members of any of the Home Builders Associations in North Texas. Through special events and media outreach, the program endeavors to make area homebuyers more aware of the program and its participants. The HBA program also includes educational seminars and is supported by the National Association of Home Builders (NAHB) and the Green Building Initiative.

After the first year of the GNBT program, the HBA reports that interest in green-built homes among builders and consumers is extraordinary. The commitment by McGuyer Homebuilders, Inc. (MHI), a volume builder constructing 800-900 homes annually, to build each of its DFW area homes to the Green Built North Texas protocol is one of the nation's largest green building commitments by a volume builder. This move accomplishes a major goal of GNBT in making green building mainstream and affordable, and not just reserved for the custom end of the market.

The Dallas HBA's Fall 2007 Green-Built Parade of Homes™ (Sept. 22 - Oct. 7 in Cross Roads, Texas) will be the first green Parade of HomesTM in North Texas and will feature the Green Built North Texas program and its components, giving attendees a firsthand look at how green construction has moved to the mainstream in North Texas.

Goals for its second year include working on guidelines for a Green Retrofit program designed for remodelers to increase the energy efficiency add green building elements to existing homes.

A component of GBNT construction guidelines under the "energy efficiency" category requires all homes to be certified by the EPA's ENERGY STAR program ENERGY STAR homes are roughly 15 percent more energy efficient than homes built to the current International Energy Conservation Code (IECC). According to the EPA, Texas easily leads the nation with more than 60,000 of the nearly 200,000 ENERGY STAR homes build nationwide. Last year, ENERGY STAR homes saved American consumers over $180 million in utility costs and 1.4 gigawatt hours of electricity.

The DFW area can boast that "Heather's Home" near Weatherford, TX--built by Ft. Worth-based Ferrier Custom Homes and designed by Dallas-based architect Gary Olp was the nation's first home to achieve the highest rating of "platinum" from Leadership in Energy and Environmental Design (LEED). The LEED Green Building Rating System for homes follows LEED's success in the commercial sector. The U.S. Green Building Council (USGBC) began the pilot test of LEED for homes in August 2005. LEEDS promotes a whole-building approach to sustainability by recognizing performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection, and indoor environmental quality. LEED provides a roadmap for measuring and documenting success for every building type and phase of a building lifecycle. The LEED rating system has four levels of green: Certified, Silver, Gold and Platinum.

In 1995 the Residential Energy Services Network (RESNET) was formed as a partnership between the national mortgage industry, Energy Rated Homes of America, and the National Association of State Energy Officials to develop a national market for home energy rating systems and energy efficient mortgages. RESNET's activities are guided by a mortgage industry steering committee composed of the leading national mortgage executives.

A study published in the Appraisal Journal documented that the market value of a home increases $20 for every $1 decrease in the annual energy costs. According to a recent analysis building a home to exceed the Model Energy Code would result in an annual savings of $170 to $425. Applying these findings to the analysis published in the Appraisal Journal would equate to an increased home market value of between $4,250 and $10,625. Fannie Mae, Freddie Mac, FHA and VA have adopted special underwriting guidelines to make financing energy efficiency less burdensome.

RESNET Ratings provide a relative energy use index called the Home Energy Rating System (HERS) Index, - a HERS Index of 100 represents the energy use of the "American Standard Building" and an Index of 0 (zero) indicates that the building uses no net purchased energy (a Zero Energy Building). In addition to rating homes on a scale of 1 to 100, they receive one to five star-plus ratings. A typical HERS evaluation costs between $100 to $300 and takes a few hours.

A HERS evaluation is like an energy audit, only more in-depth. Most HERS raters come from either the housing or energy fields and all must pass special training courses and receive certification. Each on-site HERS evaluation examines several key home components and evaluates their energy efficiency levels: thermal envelope (the home's structure, insulation, and air flow), window types, HVAC systems, appliances, geographical location and home siting fuel types and utility rates. By studying these elements, a HERS professional can calculate a home's energy cost, evaluate its overall efficiency, and recommend future changes. Data from the on-site visit is fed into a computer program, evaluated, and put into report format. Typical HERS reports will rate the house and estimate its total energy use and costs, recommend specific cost-effective energy upgrades, provide detailed information about the costs, "payback periods" and expected lifetimes of the recommendations and then re-rate the home based upon the recommendations that are added.

Currently, HERS ratings can differ from state to state because 20 years ago, many systems were created independently. However, the housing industry has been working with governmental, utility, and financial institutions to create one nationwide system. This single standard will benefit everyone, including builders, contractors, real estate and mortgage professionals, and the ultimate winners, home owners.

RECYCLING DURING REMODELING, DECONSTRUCTION INSTEAD OF DEMOLITION ARE ESSENTIALS IN THE GREEN MOVEMENT

Remodeling creates 136 million tons of waste annually, according to the EPA, which in turn makes up 20 percent of the waste in landfills. NARI, the National Association of the Remodeling Industry, calls for its members to implement green remodeling practices which focus on reducing waste during remodeling and reusing materials whenever possible.

NARI estimates that 85 to 90 percent of materials thrown out can be recycled, including lumber, sheetrock, concrete, metal, cardboard, sinks, tubs, cans and bottles, plastic, glass, batteries, and some cabinets, doors, windows and roofs.

Demolishing vs. Remodeling. If demolished, a typical, 2,000 square foot house would create 10,000 cubic feet of debris, or 127 tons. Although the cost of disposal varies depending on location, an average of $25 per ton of waste would total $3,175 for demolition of a residence. However, if a house were remodeled instead of demolished, the owners would divert 80 percent of the waste that a demolition would incur, and would save about $2,540 in disposal costs.

Deconstruction. Defined as the “disassembling of buildings to generate a supply of materials suitable for reuse in other products,” deconstruction of an average wood frame house of 2,000 square feet could produce 6,000 board feet of reusable lumber. Approximately every three square feet of lumber saved from an older structure can become one square foot of a new residence. Therefore, if deconstruction became the new standard for residential demolition, contractors could use recovered wood to build 120,000 new affordable homes annually.

The Deconstruction Institute, provides educational materials, tools and techniques, networking, case studies, articles, facts about the environmental impacts of deconstructing, and many other downloadable and interactive modules at deconstructioninstitute.com. Their data shows that recycling building materials also conserves energy. “Embodied energy” is the total amount of energy expended during the creation of a building and the products that comprise it. The amount of embodied energy contained in an average, 2,000-square-foot home, is 892 million BTUs, the equivalent of 7,826 gallons of gasoline, enough embodied energy to drive an SUV 5.5 times around the earth. Extracting raw materials from the earth consumes more energy than converting many old building materials into new, and using recycled products instead of manufacturing new ones can decrease energy consumption for steel about 50 percent and for plastic more than 90 percent.