The Taft School Faculty Home

  • Building Type : Isolated or semi-detached house
  • Construction Year : 2014
  • Delivery year : 2015
  • Address 1 - street : 06795 WATERTOWN, USA
  • Climate zone : [Dfb] Humid Continental Mild Summer, Wet All Year

  • Net Floor Area : 361 m2
  • Construction/refurbishment cost : 597 554 €
  • Cost/m2 : 1655.27 €/m2

Certifications :

  • Primary energy need :
    44.3 kWhpe/m2.year
    (Calculation method : Other )
Energy consumption
Economical buildingBuilding
< 50A
A
51 à 90B
B
91 à 150C
C
151 à 230D
D
231 à 330E
E
331 à 450F
F
> 450G
G
Energy-intensive building
This home is an excellent example of design and construction for temperate climates and energy conservation. The Taft School faculty home serves as a high performance residence and learning lab for students. In US climate zone 5, it achieved a HERS 33 excluding PV and with the 13.1 kW the HERS index is -14. Located on a quiet street adjacent to campus the existing, historic home was deconstructed and salvageable materials were donated or reused. Challenged to find high efficiency windows that were historic commission acceptable, the team installed Klearwall awnings or casements over fixed glass (to mimic double hungs) with simulated divided lites (u-values as low as 0.13). A high solar heat gain coefficient (0.58) facilitates the passive solar gain for winter months, while well designed overhangs and pergola shade summer sun. Double stud walls have 2¼” closed cell foam plus 8½” dense pack cellulose for a R-49 cavity. The exterior sheathing is R-6.6 Zip Wall System with taped seams to create the continuous air barrier. Inside the solid concrete foundation is 3” closed cell foam behind 2x4 stud walls and R-32 cellulose in the cavity. Prefabricated TJI joists frame the attic floor, an insulated “room” houses the heat recovery ventilator and ductwork, and blown in cellulose blankets it all in R-86. The house tested 0.6ACH50 proving the effectiveness of its air-tight envelope and attention to air sealing. Heating and cooling is provided by efficient air source heat pumps (9.2 HSPF, 16.5 SEER) and delivered by short duct runs which tested extremely tight. A heat pump water heater provides domestic hot water and an on-demand switch, with an occupancy sensor at each bath, ensures hot water is delivered fast and efficiently. Low flow fixtures are WaterSense certified, appliances are Energy Star labeled, and all LED lighting. A Zehnder Novus 300 (93.3% efficient) HRV supplies 112 cfm of continuous fresh air ventilation; using only 32 watts of power and runs quietly. The homeowners control the mechanical ventilation through the intuitive wall-mounted control pad to shut off or increase the ventilation. Chemicals and contaminants were reduced by using low VOC and GreenGuard certified sealants, adhesives, primers, and paints. A walk-off matt at the side entry and hardwood floors help control dirt and dust. Storm water runoff from the roof, patio, and driveway is managed by the rain garden and native landscaping is low maintenance. Taft School Director of Environmental Stewardship, Carly Borken has used the design and construction process as a teaching tool for her science classes. With access to the home monitoring system they can virtually access the homes consumption. After 12 months of utility bills the home has produced 9,868 kW more than it’s used.

Data reliability

3rd part certified

Stakeholders

    Environmental consultancy

    The Taft School

    Gil Thornfeldt, GilThornfeldt@taftschool.org

Contracting method

General Contractor

Owner approach of sustainability

Taft is educating tomorrow's leaders, and we know that as an educational institution we are role models for social change. Our sustainability challenges are similar to what many organizations face: improving energy efficiency through the physical plant, but also in the habits and minds of our community. Through a variety of initiatives by faculty and staff and through student interest and activism, the Big Red is making serious strides in going green.
Here are some of the ways Taft is working to reduce its impact on the environment: https://www.taftschool.org/non/enviro.aspx

Architectural description

More than a century has passed since Mr. Taft founded our school. While the world and the school have changed dramatically, his fundamental values endure: work hard, without regard for public acclaim; develop all your talents: academic, artistic, and athletic; and most importantly, give of yourself to others.
Horace Taft chose our school motto: Non ut sibi ministretur sed ut ministret—Not to be served but to serve. Today, Taft’s 124 faculty members educate 589 boys and girls from 33 states and 47 countries. Our beautiful 226-acre campus features facilities that rival those of many small colleges, including a library with 56,000 volumes, a 45,000 square foot science and mathematics building, student dorms, and faculty housing in the New England aesthetic of brick buildings with slate roofs.

If you had to do it again?

The attic air sealing and insulation would have been implemented differently. Spray foam was avoided so the thermal barrier at the attic floor made duct runs and air sealing more difficult.

Building users opinion

https://www.youtube.com/watch?v=YGlG2LmvEl4

Energy consumption

  • 44,30 kWhpe/m2.year
  • 76,00 kWhpe/m2.year
  • Other

  • -17,20 kWhfe/m2.year
  • Above values are in MMBtu/yr
    Heating 5.9 MMBtu/yr,
    Cooling 4.9 MMBtu/yr,
    Water Heating 3.5 MMBtu/yr,
    Lights & Appliances 27.1 MMBtu/yr,
    Photovoltaics -58.6 MMBtu/yr

Envelope performance

  • 0,10 W.m-2.K-1
  • Above Grade Walls U=0.017, Windows U=0.175, Attic U= 0.011

  • 0,12
  • I4

  • 0,44
  • Site Sage Monitoring System
    Provides up to 24 electrical circuits to be monitored with web interface; 12 Lutron Radio Ra2 lighting circuits with 2 hybrid keypads; iPad Mini, and in wall docking station. Will act as a central control and monitoring location; Provides temperature and humidly monitoring of HVAC System.
    Zehnder Novus 300 is over ridden at central control pad.

Real final energy consumption

    2 015

Systems

    • Heat pump
    • Heat pump
    • VRV Syst. (Variable refrigerant Volume)
    • Double flow heat exchanger
    • Solar photovoltaic
  • 142,00 %

Smart Building

    Since this is a single family residence there is only remote access and monitoring controls through Site Sage and Zehnder

GHG emissions

  • -1,20 KgCO2/m2/year
  • REM/Rate Modeling Software CO2 -1.2 tons/yr, SO2 -1.7 lbs/yr, NOx -1.6 lbs/yr

Indoor Air quality

    Indoor airPlus Certified

Product

    Klear Wall Windows

    Klearwall Industries

    203-689-5404

    Finishing work / Exterior joinery - Doors and Windows

    All our products are engineered with precision and crafted with care to ensure our customers get a superior quality product. Both of the domestic and commercial product ranges are suitable for passive house construction and have been certified by the Passivhaus Institut in Darmstadt, Germany

    Combining fixed windows with awnings or casements enabled the team to mimic a double hung and get approval by the local historic commission.


    ZIPS Insulated Sheathing

    Huber Engineered Woods

    andrew.collins@huber.com

    Structural work / Structure - Masonry - Facade

    For installation convenience and exceptional, long-term performance, the all-in-one ZIP System® R-Sheathing panel provides a new approach to sealing and insulating the building envelope. One panel delivers thermal, air and moisture resistance, while providing excellent strength and durability.

    Double s2x4 studs with 3 1/2" gap already reduced thermal bridging for above grade walls but ZIPS insulated sheathing was chosen for added thermal break plus the long term performance of the sheathing.

Construction and exploitation costs

  • 50 116,00
  • 597 554
  • 7 913

Energy bill

  • 203,00

Urban environment

Located on an existing educational property close to community resources both on campus and in town.

Land plot area

1 440,00 m2

Built-up area

100,00 %

Building Environmental Quality

  • indoor air quality and health
  • energy efficiency
  • renewable energies
  • maintenance
  • building process
  • products and materials
​The design and construction can be easily replicated. With an old world charm aesthetic but an open plan and modern amenities it's exciting that this home produces more energy than it uses. As an instructional tool for the environmental science class, the high school students have embraced the process, especially the continued energy monitoring. Occupant use continues to be a challenge; energy monitoring and behavioral changes are part of the solution to living net zero.

Contest categories

Energy & Temperate Climates

Energy & Temperate Climates

Users' Choice Award

Users' Choice Award

Green Building Solutions Awards 2016


Author of the page

  • Karla Butterfield

    Senior Sustainability Consultant

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