In January, Portland, Oregon-based Earth Advantage Institute announced its annual top 10 green building trends. They were identified based on discussions with policymakers, builders, developers, architects, real estate brokers, appraisers, lenders and homeowners over the latter part of 2010.
1. Affordable green. Many consumers typically associate green and energy-efficient homes and features with higher costs. However, the development of new business models, technologies and the mainstreaming of high-performance materials is bringing high-performance, healthy homes within reach of all homeowners. Leading the charge are affordable housing groups, now building and selling LEED for Homes- and Energy Star-certified homes across the country. In the existing homes market, energy upgrades are now available through new programs that include low-cost audits and utility bill-based financing.
2. Sharing and comparing home energy use. As social and purchasing sites like Facebook and Groupon add millions of more members, the sharing of home energy consumption data for rewards isn’t far behind. The website Earth Aid (www.earthaid.net) lets you track home energy use and earn rewards for energy savings from local vendors. You can also share the information with others on the site to see who can conserve the most.
3. Outcome-based energy codes. Existing buildings are responsible for most energy use and associated carbon emissions, but the prescriptive energy codes used in commercial remodels don’t encourage effective retrofitting. Compliance with energy codes is determined at permit time, using prescriptive or predictive models, and actual post-construction may never even be reviewed. Under outcome-based energy codes, owners could pursue the retrofit strategy they decide is most effective for their building and its tenants, but they’d be required to achieve a prenegotiated performance target through mandatory annual reporting.
4. Community purchasing power. Neighborhoods interested in renewable energy will increasingly band together to obtain better pricing on materials such as solar panels as well as on installation costs. Such discounts, in addition to available tax credits and cash incentives, give participants a significant cost savings.
5. “Grid-aware” appliances. Manufacturers are increasingly introducing appliances that, through sophisticated energy management capabilities and timers, can monitor and report their own electricity use and increase or decrease that use by remote command. These developments will begin establishing a smart grid infrastructure and the control applications needed to manage energy savings in our buildings and homes.
6. Accessory dwelling units. With fewer people moving or building due to financial concerns, many have chosen to stay put in their favorite area and build accessory dwelling units (ADUs). These small, independent units, which can be used for offices, studios or in-law space, are the ideal size for energy savings and sustainable construction. As detached or attached rental units, they help cities increase urban density and restrict sprawl while letting homeowners add value to their property.
7. Rethinking residential heating and cooling. Advances in applied building science have resulted in homes that are so tightly sealed and insulated that furnace-less, ductless homes are now a reality. The increasingly popular Passive House standard, for example, calls for insulation in walls and ceiling so thick that the home is actually heated by everyday activity of the occupants. Even in Energy Star-certified homes, builders are now encouraged to bring all ductwork inside the insulated envelope of the house to eliminate excess heat or cooling loss, and to use small-but-efficient furnaces and air conditioners to avoid wasting power. Geothermal heating and cooling, where piping loops are run through the ground to absorb warmth in the winter and cool air in the summer, are another option gaining broader acceptance.
8. Residential greywater use. With water shortages looming in many areas, recycling greywater—any household wastewater with the exception of toilet water—is gaining traction. Benefits include reduced water use, reduced strain on septic and stormwater systems and groundwater replenishment. Although many cities have been slow to legislate on greywater use, some communities have increased the amount of allowable greywater use for irrigation. Systems can be as simple as a pipe system draining directly into a mulch field, or they can incorporate collection tanks and pumps.
9. Small commercial certification. Ninety-five percent of commercial building starts in the United States are less than 50,000 square feet, but the bulk of current certified commercial buildings tend to be much larger. This is, in part, because of numerous “soft” costs including commissioning, energy modeling, project registration and administrative time, all of which can be prohibitively expensive for small building owners and developers. To encourage more small commercial projects to go green, a variety of alternative certification programs have sprung up.
10. Lifecycle analysis (LCA). We know quite a bit about the performance of certain materials used in high-performance home and commercial building construction, but the industry has just begun to study the effects of these materials over the course of their entire lives, from raw material extraction through disposal and decomposition. LCA examines the impact of materials over their lifetime through the lens of environmental indicators including embodied energy, solid waste, air and water pollution, and global warming potential. LCA for building materials will let architects determine what products are more sustainable and what combination of products can produce the most environmentally friendly results.
Earth Advantage Institute works with the building and design industry to help implement sustainable building practices. Its mission is to create an immediate, practical and cost-effective path to sustainability and carbon reduction in the built environment.
