2012 – Winner

Ross Family Residence

The winner of NESEA’s annual Zero Net Energy Building Award offers not only energy efficiency, but ideally also comfort, affordability, reliability, and elegance. Congratulations to everyone involved in this project. You are leading the charge on making sustainable energy practices the norm in the built environment.

Location: Amherst, MA
Architect: Coldham & Hartman Architects, Andrew Webster
Construction Management: FCM Smart Build
Construction Services: Holden Builders

Our first deep energy retrofit winner: A home for real people based on real needs

Read what the judges have to say

After intense deliberation, the judges chose to award the 2012 Net Zero Energy Award to the Ross family residence in Amherst, Massachusetts. The panel was deeply divided but ultimately selected this project for several reasons. First, this project was a Deep Energy Retrofit, the first such project to receive the NESEA award. As such, it provides an excellent example of how the construction industry should be upgrading our existing building stock to be more efficient and livable.

The Ross residence also elegantly integrated building systems that addressed the envelope, air-tightness (about 1.0ACH50 for a retrofit), passive heating opportunities, LED lighting and mechanical strategies that reduced the energy requirements to excellent levels. Based on these factors, this project eked its way past a group of other excellent, well-deserving candidates. Because of their attention to a whole-building approach, the Ross family’s PV system was not only able to meet the remaining building load but provided an additional 30% of renewable energy back to the grid.

Although some may argue that this project featured an overabundance of PV, the judges wanted to stress the importance of being a net provider if the owner has the means to do so. Moreover, because the renewable solutions are well-integrated and the home is attractive, it serves as a good example to help promote net zero energy buildings. And although the price tag and size may seem high, the designers dealt quite effectively with what they were given, choosing to save instead of tear down, and doing so for a relatively modest $141/sf.

Maybe most importantly, the design represents a home for real people, based on real needs. As a society, we need to modify the way we live for the sake of the planet. This home serves as an important mode, suggesting an incremental alternative to the way we currently live, and does so with beauty and grace.
It should be mentioned that while not all entries could be awarded first place, all had elements that were truly first-place quality. It speaks well of NESEA that the quality of the entries has increased year after year since the inception of the award.

2012 Runners – Up

Location: Putney, VT
Architect: Maclay Architects

 

Showing students that sustainability is possible—and beautiful—two years in a row

This is not just a gym…We want this to be a place where our students can learn about being environmentally responsible, so that later in life, when they are making choices, they can say, ‘It’s possible. Our gym at school did it this way’.” – Randy Smith, Putney School

The Putney School is a progressive, college preparatory school located in rural southern Vermont. In addition to classroom buildings, the campus includes a working 500-acre farm. The School’s vision for a field house was one that would support a long tradition of excellence in sports programs and serve as a central gathering space for students, while meeting aggressive sustainability goals. The Putney School Field House has the distinction of meeting NESEA’s stringent net zero criteria two years in a row, having also qualified for judging in 2011.
The two-story building features an on-site 36.8-kilowatt solar photovoltaic system, energy-efficient lighting with daylight and occupancy sensors, composting toilets, natural lighting, and earth- and human-friendly materials throughout. The first floor features a gym, a rock climbing wall, ski-waxing room, mechanical room and storage. The second floor, which serves as the central gathering space, includes bleachers that overlook the gym space, offices, locker rooms, and flex space for wellness and strength conditioning activities.
The team assessed five options consistent with the overall vision, including a Base Building Model, a High-Performance model, a Micro-load model, Carbon-neutral building; and a Net-Zero building model. The construction and operating costs for each were carefully studied, with estimates ranging from $3.5 to $5 million. Projected first year energy costs ranged from $22,500 / year to $1,200 / year. Estimated total CO2 emissions ranged from 130,000 LBs/year to 0LBs/year The net-zero option gained final approval, demonstrating how upfront investments in a super-insulated envelope, renewable energy and advanced systems create long-term predictability in future energy costs.

Super-insulation was installed and extensive air sealing was completed on the facility. To reduce heating energy use by 77% compared to the ASHRAE Standard 90.1-2007 baseline building (Appendix G.), the following high insulation levels were used: R-60 roof, R-45 walls above grade, R-20 slabs, R-20 foundation walls below grade and R-5 windows. We achieved a very low tested air leakage rate of 0.065 cfm/sq ft. of building shell at 50 pascals test pressure (0.065 cfm-50/sq.ft. shell) or 1,625cfm-50 total air leakage rate. We attribute the low air leakage to careful envelope design and execution.

Mechanical systems considered for the building included both ground-source and air-source heat pumps. The selected optimal system was an air source heat pump, as cost was the determining factor. To achieve the zero energy goal, investment in renewable energy sources was also required. To maximize performance and obtain long-term value, 36.8 kW of solar tracking collectors were installed to the north of the Field House.

Construction on the Putney School Field House began in 2007 and was completed in October 2010. The 17,500 square foot Field House is New England’s first net-zero athletic building and anticipates LEED Platinum certification from the U.S. Green Building Council.

Click here to see the poster submitted with the Putney School Field House application.

Kraus-Fabel Renovation

Location: Amherst, MA
Owner: Mary Kraus
Architect: Mary Kraus
Engineer: Marc Rosenbaum

What does it take to reach net zero? Not much, and nothing fancy

DESCRIPTION OF PROJECT:
One barrier to broader adoption of ZNE practice is the perception of ZNE as expensive and exotic. In this project we address this issue directly, and demonstrate that ZNE renovation can be straightforward and practicable, providing qualitative improvements, significant savings in energy and carbon emissions, and excellent return on investment. We started with our small, simple, relatively efficient, sun-tempered home, our half of a cohousing duplex built in 1994. What would it take to make it ZNE? Answer: Much less than I had anticipated – and nothing fancy.

Our home was built “Energy Crafted”, with 7” dense-packed cellulose walls and tight construction. Our windows were reasonably good for the time – double-pane, argon-filled, low-e casements. A sealed-combustion propane-fired boiler provided heat and hot water. An exhaust-only ventilation system kept the air fresh. Most of the lighting was CFL. The design was compact and sunny, providing a comfortable living space with three bedrooms in about 1,000 square feet of finished area (1,596 SF conditioned space.) A solar hot water system, installed on our roof in 1999, was shared with our duplex-mates. Before our ZNE renovation, our electricity use averaged 300 kwh/month; yearly propane usage was about 300 gallons. A good starting point, but nothing spectacular.

The first step on our ZNE journey followed one of my favorite sustainable design maxims, “Don’t overlook the mundane”: we bought a new refrigerator, saving an estimated 40 kwh per month. Our path to a ZNE home included:

• Careful modeling to determine strategies
• Targeted air sealing (start with a sound envelope!)
• Reducing plug loads
• New air-source heat pump to replace propane boiler
• New HRV to replace exhaust-only ventilation
• Super-insulated electric water tank as new backup for solar hot water
• 5.9 kw PV array to cover all energy uses

With PVs now powering all systems – and in spite of a record-breaking winter – our home was net energy producing this past year: 430 kwh net annual production (1.2 kwh/day, 6.5% above load). With all of this in place, our household energy use declined by 23% (using kwh equivalents for the replaced propane).

We love our new heating system. It is a qualitative improvement. One interior point-source unit provides heat for the main floor and upstairs of our cape-shaped home. It is a pleasure to sit beneath while reading on a cold day, and it keeps the whole house a comfortable temperature. A second unit serves the walk-out basement. Although we now officially have “air conditioning”, we have not used it upstairs – a south roof overhang and a deep west porch keep our home comfortable in the summer. We use the basement unit for summer dehumidification, with both qualitative improvement and significant energy savings over previous usage for that purpose.

I view energy-use reduction as an ongoing step-by-step endeavor rather than a one-time project. We plan to continue the process, including switching to LEDs, installing interior storm windows, and chipping away at plug loads. I look forward to seeing how our energy picture continues to improve, and to applying these insights in my architectural practice.

Click here to see the poster submitted with the Kraus-Fabel application.

Eliakim’s Way

Location: West Tisbury, MA
Owners: Matt Coffey and Christine Conley
Designer: South Mountain Company
Engineer: Marc Rosenbaum

Proof positive that there are no net zero buildings . . . rather, there are net zero occupants

PROJECT DESCRIPTION
As part of our quest to bring better and better quality to affordable housing, where the need is greatest, South Mountain Company designed and built a cluster of eight high-performance homes in West Tisbury, Massachusetts in 2010 for the Island Housing Trust.

The houses were designed to enable the occupants to use less energy than their solar systems produce. Half have three bedrooms (1,447 sf) and half have two bedrooms (1,251 sf); all have full basements. The houses are all-electric, each has a 5.04 kW Sunpower solar electric (PV) array, and each received LEED platinum certification.

All major energy end uses are sub-metered and carefully monitored. Our comprehensive data collection led to a detailed analysis called “Zero-Net Possible? Yes!” which has been widely published and cited. After one year, two households – a three bedroom and a two bedroom – achieved zero annual net energy, using less energy than the PV array generated. One of these – house #9 – is our submission, as the other was occupied for only 300 days during the monitoring period.

Two other households were close – within ~1,100 kWh of reaching net zero – and the remainder varied widely. We learned that there are no zero energy houses, only zero energy possible houses which, when combined with zero energy occupants, make zero energy a reality. A distinguishing characteristic of this project is that, unlike most zero-energy buildings which result from the aspirations of the clients, these occupants were chosen by lottery. They weren’t seeking zero-energy housing, they were seeking affordable housing. They got both, and we expect that more of the occupants will become zero energy families as time passes.

Click here to see the poster submitted with the Eliakim’s Way application.

The Groton

Location: Townsend, MA
Designer/Builder: Transformations, Inc.

Net positive at just $3 per square foot above stretch code prices

“The Groton” is an 1835 square foot home Transformations, Inc. built and sold in the Coppersmith Way development in Townsend, MA. It was started in late 2009 and completed in June of 2010. This home is a second generation Farmhouse model with a garage under to fit the sloped site. Many of the energy efficiency features have been honed in on though cost effective evaluations and input from many in the building science field.

The shell and energy efficient features of this home are highly repeatable. Transformations currently has 90 homes in the development and building pipeline with similar zero-energy specifications: 33 homes in Easthampton, MA for Beacon Communities; 8 homes in Devens, MA in a project for MassDevelopment; 4 homes in Princeton, MA; 17 more homes in the Coppersmith Way development in Townsend, MA; 24 units in Harvard MA; and 4 units of positive energy housing are planned for the Roxbury, Highland Street site for the Boston Redevelopment Authority.

The cost to get to zero energy has been brought down to $3 per square foot over a stretch code home with a leased PV system. At these prices, the zero energy homes can spread fast throughout Massachusetts and other states with Solar Renewable Energy Credits. It is Transformations goal to help speed this process. The typical home saves about 60% of its energy in the shell, appliances, lighting, hot water, etc. The other 40% or more is made up though the PV.

The Groton features a 7.14 kW PV system that is integrated into the surface plane of the roof for a pleasing aesthetic. We attained the look of BIPV without the cost! The roof under the PV system was recessed 8” inches to accomplish this. Black framed mono-crystalline panels further this curb appeal.

A Navien 180 instantaneous gas fired hot water heater was used in place of any solar thermal systems. It did not take up any roof space, cost $1,800 to install (as opposed to $8,500 for a solar thermal system) and used only about $43 worth gas over a 12 month period (36 Therms).
The ventilation system used was a Fantech 1504 Heat Recovery Ventilator. We exhausted the three bathrooms and supplied fresh air to the hallway on the second floor. This was done at less than half the price of the LifeBreath systems we used previously.

This “Groton” model home was cost effective to build, has excellent curb appeal and is vastly repeatable and scalable. It was built on speculation and sold for $359,900. The positive energy produced was about 1450 kW hours a year. This is enough energy to supply a plug in Prius a modest commute, 5 days a week, 50 weeks a year. With homes like these, we can solve the carbon emissions of the building sector and start to work on the transportation sector as well!

Click here to see the poster submitted for “The Groton.”

2011 Winner

Camden Friends Meetinghouse

The winner of NESEA’s annual Zero Net Energy Building Award offers not only energy efficiency, but ideally also comfort, affordability, reliability, and elegance. Congratulations to everyone involved in this project.

Location: Camden, DE
Architect:Re:Vision Architecture, Mike Cronomiz, designer and project manager
Scott Kelly, principal in charge
Contractor: Camden, DEBoss Enterprises Inc.

High quality and integrated design in a community gathering space

The judges awarded first place to this Quaker Meeting House based largely on its high quality and integrated design. The Meeting and Social Hall sits adjacent to an historic 1805 Meeting House and serves as a community gathering space designed to complement the elegant simplicity of the historic Meeting House. After the first year, the new building’s solar collectors generated almost enough energy for both buildings combined. If the social hall were left to power itself, it would provide 150% of the power it consumed, making it a net positive building. In accepting the award, architect Scott Kelly indicated that he would use the cash grant to deploy solar panels on his firm’s office building.

Text from Zero Net Energy Award application:

The Camden Friends Meeting and Social Hall sits adjacent an historic 1805 Meeting House and serves the congregation as a community gathering space designed to complement the elegant simplicity and durability of the historic Meeting House. Spaces within the multi-function annex include a large social hall, catering kitchen, archival display, community outreach rooms, and restroom facilities.

To preserve the Meeting House as the crown jewel of the site, the new annex roofline steps down in a gesture of humility; lowering as it approaches the historic meeting house and outdoor worship space. A glass core at the main entrance to the annex allows visitors to see through the new annex to the historic Meeting House when approaching the building from the rear parking lot. The clean lines of the annex, which was clad with a rain screen of salvaged cypress, and metal roof, allow the Annex to float behind the historic meeting house without upstaging it.

The building’s form and layout are designed to take advantage of passive heating, cooling, and lighting. This passive design includes a tightly sealed thermal envelope with superior insulation. The exterior wall construction is of 2×6 wood studs, bio based foam insulation, with an additional layer of insulation applied to the exterior sheathing. A rain screen keeps the water on the outside of the building and reduces the risk of condensation on the interior. The roof is constructed of structurally insulated panels (SIPS) with an average R value of 48.

Through careful design and detailing, the building starts with a low energy load. Supplemental heat is provided by a closed-loop ground source heat pump system and power by a 12Kw photovoltaic array. After the first year, the new building’s solar collectors generated almost enough energy for both buildings, leaving only 188 kW provided by the local utility company for the entire complex. If the social hall was left to power itself, it would provide 150% of the power it consumed, making it a net positive building. Equally exciting, the building exceeded its predicted energy model in both energy reduction as well as water consumption through careful operations. In terms of water, a 2,000 gallon cistern collects rainwater and stores if for use in flushing toilets and irrigation.

By design, the building is intended to have the warmth and comfort of a home. At the same time, it needs to stand up to the intensive use that comes from accommodating large groups. In this way, the building straddles the residential and commercial sectors. While the 2,864 sf building is institutional in its use, its materiality, systems, and construction methods are all applicable on both the residential and commercial scale. Camden shows that net-positive buildings are feasible for homeowners, businesses, and non-profits who have this goal.”

Click here to see the poster submitted with the Camden Friends Meeting House application.

2011 Runners-up

More models of efficiency

More models of efficiency

The Putney School Field House, Putney, VT
Kraus-Fabel Renovation, Amherst, MA
Eliakim’s Way, West Tisbury, MA
The Groton, Townsend, MA

The Putney School Field House

Any building that meets the rigorous criteria to even be considered for NESEA’s annual Zero Net Energy Building Award deserves a shout-out. These runners-up, too, are showing us the way to a sustainable built environment. They have won our admiration, if not our prize.

Knox/Thompson Residence Charlotte, VT
Livermore Home deep energy retrofit Gloucester, MA
Moomaw House Williamstown, MA
The Putney School Field House Putney, VT
Shepler Residence New Paltz, NY

Knox/Thompson Residence

Location: Charlotte, VT
Owners: Katherine Knox and James Brian Thompson, Faith and Lark Thompson
Architect: Bill Hutchins, Helicon Works
Builder: Jim Huntington, New England House Wrights
Energy consultant/installer: Kirk Herander, Vermont Solar Engineering

An off-grid farmhouse inspired by NESEA’s Green Buildings Open House

It was our intention when we started this project to create a Vermont country farmhouse. We purchased the 45 acre parcel of land the house is located on in 2001. The land previously was a large farm and our parcel was segmented into two portions, approximately 35 acres of meadow and 10 acres of woodland. We built our house in the northwest corner of the meadow for a number of reasons. We could take advantage of the woodland to our north. This serves as a wind block for the cold northwest winds that happen in Vermont in the winter months. In addition there is a hill located just 300 feet from the house site and is the highest point on our land which is an ideal spot for a wind generator. To our south, east, and west we enjoy a lovely pastoral view of the rolling terrain. We also enjoy views of Camels Hump mountain, Mt. Philo, and portions of the Adirondacks.

As a consequence of building in this spot, we were at least a half mile from the nearest utility. The picture above is taken from the road and estimates to bring utilities that far off the beaten path were eye opening to say the least. Subsequently we investigated using renewable energy to provide electricity for our home. We did research on using renewable energy and the cost associated with those. We went on the “Solar Tour” that year and discovered that people did live off electricity generated by their own system. Using both PV and a wind generator to generate electricity would seem to be the best arrangement for this northern climate. We made our decision to go with renewable energy to power our home, we would use a wood stove for heat, and propane for cooking, heating our water, and other items.

Project Design: Initial plans and architectural design for the house was completed by Bill Hutchins of Helicon Works. His ideas consist of simple building forms that are beautifully composed. Thin clap-board siding is used with trim to define windows, doors, and entrances. The informal entry to the house consists of a Mud Room and serves as a link between the garage and house. An open floor plan on the first floor consists of a farmhouse kitchen, and a main living space that form a nurturing center of the house. The woodstove is positioned in the center of the main living space and provides warmth in the colder months. The house is positioned along the east west axis with a total of twenty windows that face south. The house can thought of as a sundial, with each room receiving it’s appropriate light. This enables us to use the light from the sun for most of our lighting during the daylight hours. Our PV array is fixed to the garage roof and points 194 degrees south. We consider the house to be well insulated and it takes advantage of passive solar gain. The highest efficiency lighting and appliances were used throughout our house. The house has been Certified Energy Star Rated 5 Star by the Vermont Energy Investment Corporation.”

Click here to see the poster submitted with the Knox/Thompson Residence application.

Livermore Home deep energy retrofit

COME SEE US ON OCTOBER 13TH DURING GREEN BUILDINGS OPEN HOUSE: Click HERE!

Location: Gloucester, MA
Project designer/owner: John Livermore
Engineer: Marc Rosenbaum, PE
Lead Carpenter: Caleb Ewing
Project assistant: Bill Hallaren

Taking personal responsibility for climate change—on $50,000

The motivation for taking action to reduce our family’s carbon footprint was the understanding that carbon emissions need to be reduced by about 90% by 2030 in order to stabilize the earth’s climate, and the realization that I needed to take personal responsibility for reducing our family’s emissions. Also, I’d been in the energy efficiency business for over 20 years and felt it was time to walk the talk, taking everything I’d learned about building science over the years and applying it toward retrofitting my own house.

The purpose of performing the deep energy retrofit and renewable energy installations on the Livermore residence was to demonstrate what can be done to reduce the carbon footprint of a suburban homeowner on a budget of approximately $50,000. The overall goal was to reduce the home’s carbon footprint by 100%, and in doing so to help others by changing the current paradigm of what is possible.

The retrofit strategy has struck a balance between three key objectives:

1. Make it affordable
2. Make it feasible (use off-the-shelf technologies)
3. Make it repeatable

The house, located in Gloucester, Massachusetts, was built in 1972 and had poor energy specifications, including: Extreme air leakage (3,400cfm50), R-19 in attic, R-13 in walls, single-pane windows. Our retrofit philosophy was to reduce the building loads dramatically and then use solar energy systems to provide as much renewable energy as possible.

Key design features of the retrofit project include:

• Larsen truss wall framing system to allow installation of 5 inches of closed-cell foam (R-30).
• Gable roof extensions.
• Innovative chimney insulation system.
• Innovative basement floor and foundation wall insulation system.
• Dramatic air leakage reduction (to 500cfm50).
• R-76 attic insulation with radiant barrier.
• Triple-pane, low-E, argon, foam-filled fiberglass frame windows.
• 4.3 kilowatt photovoltaic system provides 186% of annual electricity needs.
• 3-panel solar hot water system provides over 70% of annual hot water needs.

Other energy features of house include:

• All LED and CFL lighting
• All Energy Star appliances
• Small Danish woodstove heats the entire house
• 1.125 GPM showerhead
• High-performance bath fan with 24-hour programmable controller

During the project, the Livermore house turned into a laboratory for carbon reduction strategies. The most significant behavioral modification has been hanging up clothes to dry, which has allowed dryer use to be eliminated and has resulted in approximately a 15% reduction in annual electricity usage.

The non-energy benefits of the project have been numerous and significant, including:

• Higher comfort levels
• Fewer colds and viruses
• More durable home

The house has participated in the NESEA Green Buildings tour each year since 2009.

For more information, visit www.OnThePathToSustainability.com“

Click here to see the poster submitted with the Livermore Deep Energy Retrofit application.

Moomaw House

Location: Williamstown MA
Owners: Bill and Margot Moomaw
Architect: Coldham & Hartman Architects
Engineer: Marc Rosenbaum, PE

Vernacular, low-impact building for the 21st century

The Moomaws desired first and foremost to make minimal impact on the natural ecosystem of their 14 acres, which contained fields, woods, and a one-acre pond that was home to wildlife and migrating species. They wanted a house for the 21^st century that resonated with the natural site, and was compatible with vernacular building. The roof angles, the barn-red garage and shed, the rock walls fashioned of stones from excavation, clapboards, and trim were conscious decisions to blend with the 19^thcentury agrarian tradition.

Initially they specified a highly energy efficient design using as much renewable energy and as little fossil fuel as possible. From their design team, architect Coldham and engineer Rosenbaum, they learned it would be possible, but a stretch, to achieve zero-net energy in their climate zone (7500-8000 heating degree days). During the design phase the team modeled various options for insulation, windows and energy consumption. Their contractor, Steve Haskins, embraced the concept and gave meticulous attention to insulation and air sealing.

Bill was enthusiastic about pursuing ZNE, but his wife Margot was more dubious, fearing they would compromise aesthetics to achieve the energy goal. After 2 years planning, 15 months construction, and two years of monitoring and modifying systems, they are pleased to achieve net-zero energy in a home that is beautiful and eminently livable. The 2200 square foot house was designed so the owners could work from home and accommodate numerous visitors. The couple hopes to live there for the remainder of their days. The first floor master bedroom and bathroom are wheel chair accessible. Adjacent to the main house and connected by a screen porch is a 460 square foot guesthouse for family and friends.

A long south façade provides passive solar heating. Half of the triple pane, argon-filled low E windows (U=.19) with high solar heat gain glass face south. In summer the roof overhang shades these windows. Only 15% of the glass is on the north side of the house, with the remainder divided between east and west. The location of windows optimizes day lighting.

The house utilizes a grid-connected 7.3-kilowatt PV array. Heat and hot water are provided by a 2.8-ton ground source heat pump that draws on the earth’s stored heat through 1350′ of horizontal loops. Radiant floor heating provides an exceptional degree of comfort. The house has a heat recovery ventilation system, and a Powerpipe to capture heat from shower drain water. The house is cooled in summer by natural ventilation and ceiling fans (no AC). Application specific artificial lighting is supplied by a combination of fluorescent, CFL and xenon/halogen on dimmer switches. Appliances were selected for low energy consumption (exceeding Energy Star standards). Renewable electricity is purchased from the grid as needed.

To the extent possible, materials were sourced from within 500 miles, and were chosen for recycled content (cellulose, TREX), durability (Hardiboard, standing seam metal roof, fiberglass framed windows), low environmental impact (PEX and ABS pipe, low VOC paints, native plants). New England hardwoods were chosen for flooring, kitchen cabinets, and built-ins (cherry harvested on the property). Siding for the garage and shed is local pine from managed woodlots. Upon completion, the house merited LEED Gold certification.

Click here to see the poster submitted with the Moomaw residence application.

The Putney School Field House

Location: Putney, VT
Architects: Maclay Architects

Showing students that sustainability is possible—and beautiful

This is not just a gym…We want this to be a place where our students can learn about being environmentally responsible, so that later in life, when they are making choices, they can say, ‘It’s possible. Our gym at school did it this way’.”- Randy Smith, Putney School

The Putney School is a progressive, college preparatory school located in rural southern Vermont. In addition to classroom buildings, the campus includes a working 500-acre farm. The School’s vision for a field house was one that would support a long tradition of excellence in sports programs and serve as a central gathering space for students, while meeting aggressive sustainability goals.

The two-story building features an on-site 36.8-kilowatt solar photovoltaic system, energy-efficient lighting with daylight and occupancy sensors, composting toilets, natural lighting, and earth- and human-friendly materials throughout. The first floor features a gym, a rock climbing wall, ski-waxing room, mechanical room and storage. The second floor, which serves as the central gathering space, includes bleachers that overlook the gym space, offices, locker rooms, and flex space for wellness and strength conditioning activities.

The team assessed five options consistent with the overall vision, including a Base Building Model, a High-Performance model, a Micro-load model, Carbon-neutral building; and a Net-Zero building model. The construction and operating costs for each were carefully studied, with estimates ranging from $3.5 to $5 million. Projected first year energy costs ranged from $22,500 / year to $1,200 / year. Estimated total CO2 emissions ranged from 130,000 LBs/year to 0LBs/year The net-zero option gained final approval, demonstrating how upfront investments in a super-insulated envelope, renewable energy and advanced systems create long-term predictability in future energy costs.

Super-insulation was installed and extensive air sealing was completed on the facility. To reduce heating energy use by 77% compared to the ASHRAE Standard 90.1-2007 baseline building (Appendix G.), the following high insulation levels were used: R-60 roof, R-45 walls above grade, R-20 slabs, R-20 foundation walls below grade and R-5 windows. We achieved a very low tested air leakage rate of 0.065 cfm/sq ft. of building shell at 50 pascals test pressure (0.065 cfm-50/sq.ft. shell) or 1,625cfm-50 total air leakage rate. We attribute the low air leakage to careful envelope design and execution.

Mechanical systems considered for the building included both ground-source and air-source heat pumps. The selected optimal system was an air source heat pump, as cost was the determining factor. To achieve the zero energy goal, investment in renewable energy sources was also required. To maximize performance and obtain long-term value, 36.8 kW of solar tracking collectors were installed to the north of the Field House.

Construction on the Putney School Field House began in 2007 and was completed in October 2010. The 17,500 square foot Field House is New England’s first net-zero athletic building and anticipates LEED Platinum certification from the U.S. Green Building Council.

Click here to see the poster submitted with the Putney School Fieldhouse application.

Shepler Residence

Location: New Paltz, New York
Owner: David Shepler
Builder: Greenhill Contracting

A plan for a 25-home net-zero community gets started

My home at 18 Cooper St. in New Paltz, New York, is the first of seven zero-energy (ZE) homes built by Greenhill Contracting in an attempt to create a 25-home ZE community (called Green Acres – www.greenacresnewpaltz.com). What sets this home apart from individual custom ZE homes built elsewhere is the proven repeatability of the model and a desire to maintain comfort along with performance. The other four occupied Green Acres homes have either already achieved ZE or are well on their way (5 of 7 are currently occupied). The success of my home-surpassing its ZE goal-is proving the repeatable approach to ZE construction with off-the-shelf technologies including PV, geothermal heating and cooling, and a high-performance envelope anchored by insulated concrete forms.

Envelope – All walls of the three-floor home, from foundation to roof, are built with insulated concrete forms (R-21 boosted by thermal mass effects). The slab is fully insulated with double-stacked R-20 rigid foam. The roof completes the tightly sealed envelope with 14″ of open-cell foam (R-50). The 3,237 sqft home includes a walk-out basement with generous natural light, superior insulation and ventilation.

Geothermal Heating and Cooling – A ground source heat pump (GSHP) provides all the heating and cooling needs of my home, requiring far less electricity than more conventional systems. My WaterFurnace GSHP uses a closed loop installed in a 499-ft vertical well.

Photovoltaic System (PV) – Although the home was sized to achieve ZE with an 8 kW system, I chose to install a full 10 kW in order to have extra capacity to accommodate an all-electric vehicle in the future. The SunPower system uses two 5 kW inverters installed in the mechanical room in the basement.

Windows, Light, and Appliances – I had a personal desire to maximize the natural light in the house without compromising the ZE pursuit. All windows are triple-paned, krypton-filled rated at U-value 0.22 or better. The true-solar-south facing side receives the largest share of windows to take advantage of passive solar effects, while the north side has the fewest. Rarely must a bulb be turned on during daytime due to the abundance of natural light. The kitchen uses nothing but LED lighting and the rest of the home uses CFLs. All appliances in the home (including a second full refrigerator and electric induction stove for a live-in tenant) are high performance, Energy Star approved, and the entertainment center is switched at the wall to eliminate phantom loads.

Other Notes – Although I installed a modern woodstove for aesthetic reasons, I have not used it, allowing me to fully evaluate the home without it. My living habits are typical: I use the dryer for my laundry and keep the home comfortable (69˚F winter, 75˚F summer). My LEED-Silver home has many comfort features: granite countertops, floating stairs, deep sills, under-lit cable rails, high-end cabinets, dual-flush toilets, radiant-heat floors in master bath, and vaulted ceiling.”

Click here to read an article from Solar Today about this project.

Click here to see the poster submitted with the Shepler residence application.

2010 Winner

Montague Urban Homestead

The winner of NESEA’s annual Zero Net Energy Building Award offers not only energy efficiency, but ideally also comfort, affordability, reliability, and elegance. Congratulations to everyone involved in this project.

Location: Montague, MA
Owner/designer: Doug Stephens and Tina Clarke
Contractor: Bick Corsa

 

 

 

 

2010 Runners-up

More models of efficiency

Any building that meets the rigorous criteria to even be considered for NESEA’s annual Zero Net Energy Building Award deserves a shout-out. These runners-up, too, are showing us the way to a sustainable built environment. They won our admiration, if not our prize.

Location: Northampton, MA
Owner: Caroline Hagadorn
Architect: Kraus-Fitch Architects