Page 38 - Green Builder Sept-Oct 2020 Issue
P. 38

DOE Annual Building Science Roundup A BETTER WAY



                   SUN SEEKER







                   This ‘Panacea’ is a cure-all for a cold climate’s

                   high energy costs.



                                  HEN  THRIVE  HOME     year). For some homeowners, this means the
                                  Builders hosts “meet your   only cost on the electric bill is the monthly
                                  neighbors” parties for   service charge.
                                  owners of the homes in   Even without photovoltaics, the two-story,
                   W its “Panacea Collection”           ¡,”¢“ square foot home is so e‰cient that it
                   in Denver, Colorado, the homeowners rave   would achieve a calculated HERS score of
                   about all the things they love about their   ¢•, while typical new homes built to code
                   new homes: low energy bills, the continuous   would have HERS scores of about ž„ to ”„„.
                   fresh air, walls that don’t shake during ƒ„   To achieve the high energy-efficiency
                   mile per hour wind storms, and hot water   requirements of this cold climate location,
                   that doesn’t run out, even when a lot of   Thrive  used  WUFI  hygrothermic
                   relatives come to visit. They mention how   modeling to design a wall that provides a
                   allergy symptoms seem to go away and   high wall insulation value of R-¢„ with a
                   asthma attacks are far fewer. They also talk   low risk of moisture accumulation. Thrive
                   about the open, light-‡lled interiors and the   chose double-wall construction consisting
                   even temperatures.                   of two “-by-¢ “¢-inch on-center walls with
                     What they may be less aware of is the   staggered studs. The walls were spaced “.¡
                   advanced technology and building science   inches apart to provide a œ.¡-inch-deep wall
                   know-how that went into making these   cavity that is stu£ed with blown ‡berglass
                   high-performance homes. Their builder,   to  provide  a  thick  blanket  of  thermal
                   on the other hand, knows all about high   protection while acting as a natural sound
                   e‰ciency. Thrive Home Builders is a multi-  dampener, ensuring outside noise is kept
                   award winning production home builder   outside. Crews installed oriented strand
                   in the Denver area, which has certi‡ed at   board (OSB) sheathing and used a sprayer-
                   least ƒƒŠ homes to the U.S. Department of   applied sealant to seal all seams. Rim joists
                   Energy (DOE)’s Zero Energy Ready Home   were air sealed and insulated with spray
                   (ZERH) Program since “„”•. That’s more   foam. Textured house wrap provided a   walls accentuate the classic jamb and case
                   homes than any other home builder in   drainage plane behind the ‡ber cement and   trim around the windows, while providing
                   the country, except Mandalay Homes of   brick veneer siding.              a high level of ‡nish and usable window
                   Prescott, Arizona.                     Thrive employs internal and third-party   sills. The ENERGY STAR windows are
                                                        quality checks on all of its homes, speci‡cally   carefully placed throughout the home to
                   GETTING READY FOR SUN                focused on water management, to ensure the   take advantage of natural daylight. The
                   POWER                                wall assembly installation is durable and   double-pane,  argon-filled,  vinyl-framed
                   The DOE program doesn’t require solar   will remain e£ective for the life of the home.  windows, provide an insulating U-factor of
                   panels to be installed on the home; it just                               „.“¡ and a solar heat gain coe‰cient (SHGC)
                   requires that the home be ready for them.   UTILITY BILL BARRIERS         of „.“„, meaning the windows perform well
                   Thrive installed solar panels and battery   The home’s mid-century modern design   at preventing solar heat gain.
                   storage. With the addition of œ.œ“ kilowatts   helps to achieve the utility bill savings, with   The home’s vented attic was constructed
                   (kW) of rooftop solar panels and a ƒ-kW Tesla   a broad low-sloped roof that provides plenty   with ”¢-inch raised-heel trusses to allow
                   Powerwall   for storing energy, the Panacea   of space for PV panels, high windows to   space for the full depth of insulation over
                   homes achieve an impressive Home Energy   bring in daylight, and deep roof overhangs   the top plates. All of the top plates were air
                   Rating System (HERS) score of ž, which is   to keep out unwanted summer solar heat   sealed with a sprayer-applied sealant, before
                   essentially net zero energy performance   gains.                          installing R-¡„ of blown ‡berglass over the
                   (meaning a home that produces about as   In  addition  to  reducing  noise  and   ceiling deck. In cathedral ceiling sections,
                   much energy as it uses over the course of the   increasing home comfort, the extra-thick   R-¢œ of batt insulation was installed.

                   36  GREEN BUILDER September/October 2020                                               www.greenbuildermedia.com




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