Net Zero Demo Home Uses Heat Mirror Glass
When preparing to build his home on the Stanford University campus, professor of civil and environmental engineering Mark Jacobson sought to meld mid-century modern design with net-zero energy performance.
Upon commencing the project, Jacobson, a climate and energy scientist and the current director of Stanford’s Atmosphere and Energy program, was well-versed on the requirements of California’s 2020 Zero Net Energy (ZNE) new home building requirements.
“The NZE framework outlines aggressive energy efficiency performance standards for building projects in California, and is likely to become the standard by which new building codes throughout the U.S. are modeled,” said Jacobson. “As part of California’s revisions to Title 24 in 2014, NZE sets the pace for all residential buildings in the state to operate at net-zero energy levels by 2020, with its commercial buildings to follow suit by 2030.”
Additionally, Jacobson and his team needed to employ building methods and materials providing the necessary seismic resistance required in the state of California.
Following extensive research, Jacobson was able to identify a solution in Quebec, Canada-based homebuilder BONE Structure, which specializes in the design and manufacture of steel-frame, net-zero energy ready homebuilding systems. These systems – engineered around the idea that while the “framework” of every human body consists of 206 bones, no two humans are exactly alike in shape or size – allow for virtually unlimited home design customization possibilities.
Read more about the ZNE model home.
“The steel frame system allows for exciting design features that would not be possible using traditional building methods,” Jacobson explained. “Among many attributes, interior spaces and window lines can run up to 25 feet between columns, eliminating need for the numerous load-bearing interior walls required by traditional building. This translates to a great deal of potential in achieving modern home design goals, including sleek, minimalistic lines, open interior concepts, and expansive exterior window walls.”
BONE Structure homes are assembled with a single type of self-tapping screw, designed to join laser-cut steel framing components via use of a simple battery-powered drill. Their ZNE-compliant performance characteristics are the result of incorporating pre-cut, polystyrene wall panels, pre-cut plywood roofing with foam insulation, and foam roofing topped by a layer of polyurethane. Designed to operate on 100-percent electricity, BONE Structure homes also feature a Tesla Powerwall energy storage system and Wall Connector auto charger, and a Nest Learning Thermostat.
To align with NZE-level building envelope performance requirements, while also delivering on Jacobson’s modern design goals, BONE Structure recommended incorporation of windows from Alpen High Performance Products.
“Alpen windows provided the ideal solution, both in their modern and streamlined design features, and in performance characteristics that make them some of the most energy efficient windows available – throughout North America, and the world over,” said Charles Bovet, vice president of operations for BONE Structure.
Alpen 525 Series single-film windows were specified for the home’s 35 window openings, along with three sets of four-panel Alpen 525 Series sliding doors.
“With a 1 3/8-in. glazing pocket, our 525 Series windows and doors easily accommodate the larger glass surfaces typically desired in this type of modern home design,” explained Dave Maier, window solution specialist at Alpen and project manager for the Jacobson residence.
Featuring Alpenglass, which combines Heat Mirror suspended coated film with high-performance low-e glass technology, Alpen 525 Series fiberglass windows and doors can deliver up to R-5.9 thermal resistance performance. Their unique design offers reduced interior condensation and 99.5-percent UV protection, and ensures warmer windows in the winter and cooler windows in the summer.
“Offering roughly double the energy performance of what would otherwise be used for this project, Alpen 525 Series windows and doors remain a terrific value leader,” Maier said. “Provided at a competitive price point, the 525 Series windows and doors also superseded the project’s energy performance requirements when integrated within the BONE Structure building framework.”
All windows and doors were successfully installed at the Jacobson home this spring, and according to Alpen president Brad Begin, mark the first of many hoped-for collaborative initiatives between Alpen and BONE Structure.
“The Jacobson residence project creates an ideal platform from which to launch our further collaboration with BONE Structure, as it clearly exemplifies the energy efficiency advantages of combining Alpen windows and doors within the BONE Structure building framework solution,” said Begin. “The modern BONE Structure home designs, and particularly their call for large exterior glazing expanses, provide a great opportunity for high gain/low gain window and door system tuning, which translates to an ideal passive solar solution, and also provides maximum year-round occupant comfort.”
Slated for completion by the end of 2016, Jacobson’s 3,200-square-foot home will be the first of what BONE Structure expects to be many more net-zero energy ready housing projects in the U.S. The company planted official U.S. roots this year in its establishment of a San Francisco office, and is currently involved in 31 projects in the Bay Area alone.
“We’re incredibly enthusiastic about the potential for this concept in the U.S., and the opportunities to be realized in partnering with like-minded U.S.-based companies such as Alpen,” Bovet said. “The home design trend of ‘modern meets high-performance,’ presently in high demand across Alpen’s close-to-home Colorado Front Range and Western Slope regions, is one on which we are eager to capitalize with the BONE Structure solution.”
Read more about energy-efficient windows.