Ten Predictions for U.S. High-performance Buildings in 2014
Hammer & Hand’s Sam Hagerman, Skylar Swinford and Dan Whitmore enjoy a unique view of the U.S. high performance green building scene. One could call it “binocular”, combining on-the-ground experience with a bird’s-eye policy perspective.
These three Passive House consultants and builders have built some of the most notable high-performance green building projects around, including the Glasswood commercial Passive House retrofit (the first such project in North America). They’re also involved in the high performance building policy arena. Hagerman and Whitmore serve on the board of the national Passive House Alliance US, where Hagerman just finished his three-year term as inaugural president. [View a video, "Passive House Guidelines for Commercial Building Retrofits", featuring Hagerman on retrofitTV under "Services/Organizations".] Whitmore travels throughout the country instructing builders about high-performance techniques as co-leader of the Passive House Institute US builders training program and serves as Treasurer of Passive House Northwest. Swinford consults on dozens of high-performance projects across the continent, from large multifamily homes and office buildings to single-family dwellings. All three are sought-after speakers at regional and national conferences.
So, given their unique perch, how do they expect U.S. high-performance building to evolve in 2014? I posed the question, and they made these 10 prognostications:
1. Focus will move beyond Net Zero Energy to Net Positive Energy buildings.
While Net Zero Energy (NZE) use for buildings is laudable, it can set up a zero-sum game that pits onsite energy conservation (building energy performance and energy efficiency) against onsite renewable energy production (solar photovoltaic arrays). After all, if your goal is zero, then the more production you achieve, the less conservation you need to worry about. And vice versa. But energy conservation and renewable energy production are “goods” we should be incentivizing. Three trends will begin moving the high-performance building industry toward Net Positive Energy (NPE) buildings:
- Falling prices for photovoltaic panels to make energy production more feasible.
- Increasing viability and availability of electric vehicles to harness surplus energy production and compete with buildings for electricity.
- The emergence of market mechanisms that reward onsite energy conservation and production (see next point).
2. Market mechanisms that reward energy conservation and renewable energy production will flourish.
Market-based tools like Feed In Tariffs (to allow building owners/operators to sell excess energy back to the grid), Carbon Offsets (to reward building owners/operators for reductions in carbon footprint) and Metered Energy Efficiency Transactions (to allow investors in building energy efficiency to sell “negawatts” back to the utility, being piloted by the Bullitt Center and Seattle City Light) will continue to gain ground in 2014. The joint climate pact signed by California, Oregon, Washington and British Columbia in October 2013 helps set the stage for significant movement in 2014. See this Greentech Media article about Metered Energy Efficiency Transactions.
3. Building energy codes will move away from prescriptive rules toward performance-based measures.
High-performance building depends on site-specific solutions with varying approaches depending on microclimate, solar access, humidity, wind exposure and a host of other factors. The cookie-cutter approach dictated by prescriptive energy code doesn’t allow for this flexibility and is therefore an obstacle to high-performance building. Jurisdictions across the U.S. are increasingly recognizing this and shifting to performance-based rules in building energy code. Prescriptive health and safety rules still apply, but actual building energy use intensity (EUI) becomes the measure of compliance to energy-efficiency benchmarks, not dictates about insulation thickness. The city of Seattle leads the charge at the municipal scale, and the states of California and Washington have taken important first steps at the state level. The US Department of Energy continues to push the envelope through its work on the International Energy Conservation Code. Expect the trend toward performance measures to continue in 2014 as the limitations of prescriptive code become more and more obvious to policy makers.
4. CO2 heat pumps will help transform heating and cooling performance.
New technology will continue to drive the development of the U.S. high-performance building industry, with CO2 heat pumps making an entrance into the North American marketplace. These heating and cooling units, already common in Europe and Japan, use carbon dioxide as their refrigerant, and bring these benefits:
- Earth-friendly because of lower global warming potential (GWP). The R410A refrigerant commonly found in heat pumps has a GWP of a whopping 2088. That’s 2088 times more potent than that of CO2.
- Move more energy more efficiently.
- Work in much colder climates without the steep performance curve drop-offs seen with other heat pumps.
5. U.S.-made high-performance windows will continue to make high-performance building easier here.
As more U.S. window manufacturers begin producing high-performance windows domestically in 2014, the availability and affordability of super-efficient fenestration will help make the economics of high-performance building projects “pencil”. The quality of these domestically produced windows will also continue to improve. Many existing window designs have pushed performance (U-values) as far as they can with existing “American” profiles, so more will move to a European sash and frame design with better glass, better hardware, thicker frames to accommodate thicker insulated glazing units and better thermal breaks.
Just a few years ago we had access to just a few high-end Passivhaus European window manufacturers. Today more than a dozen European window manufacturers have active distribution channels in the U.S. and more manufacturers are jumping on board to capitalize on the growing demand for high-performance windows in North America. This competition has led to more aggressive pricing and a wide product selection. More importantly, this growing trend has caught the attention of many North American window manufacturers who are now taking the steps to develop higher-performing systems.
6. Builders and designers of high-performance homes will design ventilation systems with a focus on quality of ventilation rather than just quantity.
Gone are the days of installing a couple of bath fans on timers to provide ventilation for a building’s occupants. Thanks to the building science controversy sparked by the latest ASHRAE 62.2 standard and its quantity-over-quality approach, Dr. Joe Lstiburek of Building Science Corp. has spearheaded the charge for ventilation strategies and systems that understand the importance of ventilation quality (controlling the source of makeup air and mixing and distributing fresh air effectively). For example, a house relying on a conventional single-point exhaust to provide continuous ventilation would need to exhaust nearly three times the cubic feet per minute of air compared to that of a high-performance home with a distributed and balanced heat recovery ventilator. When it comes to ventilation the name of the game is quality not quantity.
7. The U.S.-led move to make Passive House more climate-specific will improve performance at micro and macro levels.
A persistent critique of the Passive House approach to high-performance building is that while it applies well to moderate climates, it is ill-suited to the extremes: warm and humid “latent load” climates and extremely cold climates. In the past year the Passive House Institute US began spearheading the effort to make the Passive House standard more sensitive to the diverse climates found across the U.S., including partnerships with Building Science Corp. and the U.S. Department of Energy. This effort will bear fruit in 2014, helping to guide successful high-performance building in the American South and across the northern portion of the continent. This promises to elevate the overall performance of North American high-performance building as a whole.
8. Passive House competition will result in better software tools for high-performance building practitioners.
While much has been made of the Passive House split between “the Americans” (Passive House Institute US) and “the Germans” (Passivhaus Institut), competition between the two organizations has led to important innovations that will benefit high-performance building practitioners in 2014. The new software tools WUFI Passive and PHPP v.8 are major improvements. WUFI-P, for example, now makes it possible to recognize and account for latent loads and user comfort, not just energy savings. Hourly simulations allow designers to optimize with pinpoint accuracy, ensuring that their high-performance designs perform well for their human occupants.
9. Europe’s push to eliminate thermal bridges in buildings will make high performance building more mainstream in the U.S., too.
Europe is pushing hard to eliminate thermal bridges (building elements that transfer heat or cool energy through the building envelope), resulting in a wave of new user-friendly software tools for calculating thermal bridging. This development has brought what was once a highly technical, niche element of high-performance building into the mainstream in Europe. These same tools apply equally well in the U.S. and promise to make the battle against thermal bridges easier to win for U.S. designers in 2014. Additionally, the materials needed to readily build without these thermal bridges are improving in design, pricing and availability and are beginning to be included in the North American market.
10. China’s interest in high-performance building will propel the U.S. market.
While still nascent, China’s move toward high-performance, energy-conserving structures and building envelopes will have far-reaching impacts. From demand for U.S.-manufactured building components to supply of Chinese-made ones, the U.S. high-performance building industry stands to gain when the world’s second largest economy puts its weight behind building energy conservation.