What is the Living Building Challenge™?
Status: Certified 'Net Zero Energy Building'
Location: Ann Arbor, MI, USA
Size of House: 1500 sf living space* (*total conditioned area within thermal envelope is 2600 sf)
Climate Zone: Cold Climate / USDA 6a
Electrical: Dan Delzoppo
Lighting Design: Matt Grocoff
Historic Restoration: THRIVE/Matt Grocoff
Landscape: Drew Laithin
Interior Design: Matt Grocoff
HVAC & Plumbing: Haley Mechanical
Net Zero Water: UM BLUElab
Electrical: Dan Delzoppo
Lighting Design: Matt Grocoff
Solar Electric: MES/SolarSpecialists
Window Restoration: Wood Window Repair
Rain Harvest Gutters: GreenOakGutters
Kitchen Cabinetry: Branch Hill Joinery
Local Sawyer: Tervol Wood Products
Farmers Insulation: Farmers Insulation
Arbor Insulation: Arbor Insulation
When Kelly and I first bought the Victorian-era Gauss house, it was our dream house . . . complete with lead paint, asbestos siding, zero insulation (except for a layer of newspaper in the attic dated 1902), a 1957 gas furnace, a fridge from 1989, and carpet over the old heart pine floors.
We were inspired by the vision of Ray Anderson, the self-proclaimed “radical industrialist” and Chairman and Founder of Interface, Inc. the world’s largest manufacturer of commercial carpets. In 1994, after reading Paul Hawken’s “The Ecology of Commerce” Ray experienced an epiphany and challenged his company to begin a journey toward a positive environmental footprint. We set out on a Mission Zero of our own to create a home that would harvest 100% of its own energy, 100% of its own water, create zero waste and ultimately become a restorative part of our community.
Just after we purchased our home, I had the great fortune of meeting another visionary, Jason McLennan. In August 2006, Jason publicly announced The Living Building Challenge 1.0, widely considered the world’s most progressive and stringent green building program.
"The Living Building Challenge™ is the built environment's most rigorous performance standard. It calls for the creation of building projects at all scales that operate as cleanly, beautifully and efficiently as nature's architecture. To be certified under the Challenge, projects must meet a series of ambitious performance requirements over a minimum of 12 months of continuous occupancy."
The Challenge is comprised of seven performance categories called Petals: Place, Water, Energy, Health & Happiness, Materials, Equity and Beauty. Petals are subdivided into a total of twenty Imperatives, each of which focuses on a specific sphere of influence.
In January 2015, our home became the fourth home to achieve Net Zero Energy Building Certification under the strict standards of the Living Building Challenge. Working with students from the University of Michigan College of Engineering BLUElab Living Building Challenge Team, we are working on Petal Certification to achieve Net Positive Water. The home is also a Greenstar Certified remodel.
Photos by Kevin Miyazaki
With over 130 million existing homes in America, half built before 1974, we wanted to restore a neglected old home rather than buying new. We wanted to preserve the heritage, the story of place and the beauty of the home without expanding the footprint.
The Mission Zero House, a 1901 historic preservation in Ann Arbor, MI is a 1,500 sf home in a cold climate with four distinct seasons and temperatures ranging from 95°F to -20°F. Practically, there was minimal improvements that could be made to the home's thermal envelope. To achieve net zero energy attention was focused on optimizing energy productivity in the home through the use of efficient systems, efficient appliances and control systems.
We set out to restore our Victorian-era home to net zero energy, net zero water and ultimately make the building a restorative part of the community in both spirit and ecology. The project was a historic rehabilitation within the guidelines of the Secretary of Interior Standards for Historic Preservation. It was not a gut rehab. A casual visitor to our home would never recognize the house as a “green” house. And that’s the point. We’ve restored as much as we could and used salvaged materials and antiques for the rest. When buying new was the only option, we looked for recycled content. Only the solar panels on the roof will give away our secret that this is no ordinary historic home.
Annual Energy Use During Documentation Period (July 15, 2013 - July 15, 2014)
Actual: 8676 kWh/yr
Targeted: 8,535 kWh/yr
Actual Energy Production During Documentation Period:
Note: Despite record breaking low temperatures during the winter season of the performance documentation period, the home still produced an energy surplus.
Renewable Energy System
8.1kW DC (36 225W Sunpower SPR-225-BLK solar panels + 36 individual Enphase microinverters). The system produced 8,939kWh during the 12 month documentation period.
The project was a historic rehabilitation within the guidelines of the Secretary of Interior Standards for Historic Preservation. This was not a gut rehab. Importantly, the Grocoffs personally desired to preserve the heritage, the story of place and the beauty of the home without expanding the footprint. Therefore, removal, replacement or addition of walls or windows or expanding the home’s footprint was not considered.
Built in 1901, the home had good solar orientation, eaves that provide summer shade for the second floor windows, passive stack effect from operable basement and attic windows, and large south-facing windows. These features were retained and restored to achieve their original function.
Practically, there was minimal improvements that could be made to the homes thermal envelope. To achieve net zero energy attention was focused on optimizing energy productivity in the home through the use of efficient systems, efficient appliances and control systems.
Insulation and Sealing:
Windows: The existing original windows are single-pane assemblies with wood framing. To improve the energy efficiency of the house, Lorri Sipes, FAIA, a wood window repair expert, restored and weatherstripped the original sashes and hardware. Trapp low-e storms were added to the exterior.
Air Changes per Hour @ 50 Pa (ACH50) was reduced from 15.70 ACH50 before the window restoration to 4.75 ACH50 after restoration and installation of exterior storm windows.
Wall Insulation Retrofit: On the exterior, the asbestos siding, installed in 1947, was removed to reveal the original wood clapboard siding. Two rows of clapboard were carefully removed. Holes were drilled through the wood lathe to allow for filling the above-grade balloon-frame walls with R-13 dense-pack blown cellulose insulation. The clapboards were replaced and the original exterior wood was restored and painted. Limited by the 2x4 width of the original framing, the walls achieve a value of only R-15 including the plaster walls and exterior wood clapboard.
Basement: The basement foundation walls are made of cut stone block and is partially below grade. The rim joist cavity was filled with spray foam. However, the stone foundation walls were left uninsulated. The basement is partially conditioned and used for laundry and storage.
Attic: The attic was converted from an uninsulated, poorly vented space (vented with gable windows) to a cathedralized, unvented space using open cell Demilec Sealection 500 spray foam, achieving approximately R-29.
EcoSmart Insulated cellular shades are used on the interior of the windows.