How Bates builds green
Green Building at Bates
The transformation of Hedge Hall and Roger Williams Hall into new academic spaces is the fourth major construction project to follow the College’s green building guidelines, adopted in 2006.
Under the College’s green building guidelines, Bates agrees to pursue, at a minimum, the equivalent of LEED Silver certification for each new construction and renovation project on campus.
- Bates’ first three green construction projects were the new student residence at 280 College Street, Alumni Walk and the New Dining Commons.
- The current Hedge / Roger Williams project is the first application of Bates’ green building principles to existing College buildings.
- Green building saves Bates money. According to accepted industry standards, it adds about 2 percent to construction costs with a payback period of about six years.
To achieve green-building goals. the Hedge / Roger Williams project will focus on achieving energy efficiency, a strategy that saves money while also supporting Bates’ efforts to achieve climate neutrality by 2020.
Currently, 90 percent of greenhouse gas emissions at Bates come from buildings and their use of heat, electricity and domestic hot water. By implementing various green-building measures, such as daylighting techniques, motion sensor switches, efficient heating and ventilation systems, will reduce energy consumption by an estimated 32 percent.
Green Strategy for Hedge and Roger Williams
Hedge and Roger Williams are currently highly inefficient: Their multi-wythe brick walls are uninsulated, and heat radiating from their roofs quickly melts snow.
Each will be insulated from the inside (preserving the historic exterior brickwork), and after renovations Hedge and Roger Williams will be up to 30 percent more efficient than what is required by ASTM International, a major standards-development organization.
|After renovations, Hedge and Roger Williams will be up to 30 percent more efficient than what is required.|
“These two buildings have been extensively modeled so renovations meet demanding design and efficiency goals,” says Ryan Kanteres of the design firm JSA, which will specify very strict air-leakage tolerances for the finished building envelopes.
By achieving a highly insulated and high-performing envelope for both buildings, Bates can make the best use of “very efficient” green features, says Kanteres.
Yet the new interior envelopes must not have too much insulating power, says Kantares. A super-insulated envelope, he explains, would allow the exterior bricks, which have been kept warm by escaping heat in the past century, to suffer damaging freeze-thaw cycles. “That’s too much of a risk,” Kanteres says. “So we will maintaining a similar structural performance of the brick to what it has been doing for a hundred years.”
- Hydronic heating and cooling Hydronic units use hot and cold water to control air temperature. Modern units resemble traditional baseboard heaters but instead are ceiling-mounted. The units are silent and offer individual zone control, with much greater energy efficiency and less noise than conventional HVAC units that use large amounts of electricity to run blowers.
- Measurement and verification (optional depending on budget) This Web-based process allows students, faculty and staff to see and monitor a building’s energy use and real-time carbon footprint.
- Natural daylighting Thoughtful window placement makes effective use of natural light, reducing the need for electric lighting. For example, new dormers will be installed on the east side of Hedge Hall. Also on the east side, windows on the first floor whose upper third has been bricked over will be restored to their original tall dimensions.
- Occupancy sensors to control lighting Because studies show that even careful users are not diligent about controlling the lighting in public and private spaces, occupancy sensors reduce the time lights are left on when no one is present.
- CO2 sensing Regulates the amount of outside air being introduced and prevents over-ventilation.
- Smart windows Indicator lights inform occupants when opening a window will aid heating or cooling.
- Low-emitting materials and finishes These reduce pollutants inside the buildings, specifically volatile organic compounds such as carcinogens released by some paint, finishes, synthetic foams, fabrics and stains.
- Recycled materials Contractors will use certified-green building materials and will recycle debris during construction.
- Low-flow water fixtures Contractors will use low-flow faucets, toilets and showerheads.
- Salvaged items Heavy timber beams are being reused as window sills in various classrooms; decorative elements, including a Corinthian pilaster column capital from Roger Williams discovered during interior gutting last year.
- Solar heating (optional depending on budget) Solar panels on the Hedge roof would supply domestic hot water.
- Enhanced lighting controls Digital photo sensors can detect daylight levels and automatically adjust the output level of electric lighting.
- Mitigating solar gains The Roger Williams addition includes a glass wall enclosing the five-story stairway. To mitigate the excessive heat from the windows, this vertical space will feature motorized windows at top and bottom to make good use of the natural chimney ventilation effect created by the vertical space.
Climate Action Plan
Bates’ plans to seek College-wide climate neutrality by 2020. Here’s how.
Read about therange of sustainability initiatives.
See the green features of prior construction projects, 2006 to 2008.