Bowdoin College in Brunswick, Maine, has a long history of dedication to the arts and environment. The “Offer of the College,” written in 1885, begins, “To be at home in all lands and all ages; to count Nature a familiar acquaintance and Art an intimate friend.” •
The college always has endeavored to preserve and present its impressive collection of European and American art. The Bowdoin College Museum of Art was commissioned in 1891 to serve this purpose. The Renaissance-revival building was designed by McKim, Mead and White, a well-respected East-coast firm of the late 19th and early 20th centuries whose other designs include the West and East Wings of the White House in Washington, D.C. •
The building’s exterior has changed little since its dedication in 1894. It has become a fixture at the college and a landmark historic building in the state of Maine. A few interior and HVAC renovations have been made during the years, but outdated environmental control systems and a shortage of usable storage and exhibit space in the museum were making it increasingly difficult for the college to care for its artistic treasures. The college needed to find a way to meet the modern needs of its art collection while maintaining respect for the history of this classic structure.
A DELICATE REHAB
The college turned to Boston architecture firm Machado and Silvetti Associates and Portland, Maine-based Consigli Construction Co. Inc., a general contractor well known for its historic restoration work. Early project goals were to upgrade temperature and humidity controls, create universal access, and add new galleries and enhanced teaching spaces.
“They’ve got an incredible collection and it’s not very well known because they didn’t have the facilities to properly store or display the artwork,” says Nick Collins, project manager for Consigli Construction. “A large part of the collection was at other institutions, in museum storage facilities, or huddled in a small area of the building that had the best control over temperature and humidity.”
Achieving the proper environmental parameters for the preservation of the college’s art collection was a key component to the renovation project. The goal was to maintain an internal atmosphere of 70 F (21 C) with 50 percent humidity and a plus- or minus-5 percent variation in either direction for temperature and humidity. That was easier said than done in an uninsulated brick building that has battled harsh Maine winters for more than a century.
“It was quite a challenge to shoehorn a modern, high-flow, low-velocity HVAC system into a building that was built in the late 1800s,” Collins explains. “This was a building that, as far as the interior fit-out went, was well beyond its useful life. On the inside it was a dark, dank building.”
As the scope of the project came into full focus, the design team found itself faced with a complete gut rehab and expansion that required attention to energy efficiency and all the delicacy involved with historic preservation. This complex set of challenges inspired innovation on a number of fronts.
DOWN AND OUT
Because the building is a state landmark, no real changes could be made to the façade and any addition would have to carefully complement the existing structure without upstaging it. “We could not tamper with the exterior of the original building. That was an absolute no-no,” Collins says. “We were, however, able to put an addition on the back.”
Anything that would connect to the main building would have to be very sensitive in its design. “We worked closely with Bowdoin College and the Maine Historic Preservation Commission [Augusta] to come up with an appropriate response for the rear addition,” says Conrad Ello, formerly a senior associate at Machado and Silvetti Associates, now principal of Oudens Ello Architecture in Boston. “It’s a very deferential response to the historic building. It has the same brick patterning, but the details are pared down so there’s a distinction between the old and new.”
An updated entrance was added to embrace a modern sensibility. “The entrance pavilion is connected underground and physically separated above grade,” Ello explains. “It is a 21st-century structure made out of glass and bronze. It’s dramatic but small enough to be respectful to the main building. Pairing the new entrance pavilion with the historic building is reflective of the two-sided nature of the collection, which is modern and historic.”
While the exterior of the building was off limits, the interior was another story entirely. “We completely gutted the interior. If it didn’t hold up the building, we took it out,” Collins recalls. ”And because much of the museum is below grade, we were able to expand the square footage of the building by adding a large, below-grade expansion to the north.”
This was a clever, if challenging, solution to the museum’s space problems. By increasing the square footage of the basement, green space on the grounds above could be preserved and the view of the original building from the campus quad could remain virtually untouched. However, the original basement ceilings were only about 8-feet (2.4-m) high. The foundation had to be lowered 4 feet (1.2 m) to provide greater overhead space.
Months of painstaking digging and careful monitoring were required as the old building settled onto its new foundation. Workers underpinned the structure and excavated beneath the building’s rubble foundation. The voids were filled with reinforced concrete to ensure the original stone and granite foundation would remain stable. This massive technical undertaking transformed a cramped basement space into an airy, open gallery accessible from the new entrance pavilion.
“Visitors walk into the cubed glass entry and go directly downstairs,” Collins explains. “The above-grade footprint is small, but there is a lot of gallery space downstairs. We were able to almost double the square footage of the building while having a minimal increase to the above-grade footprint.”
THE AIR IN THERE
Having addressed the museum’s space concerns, heating and cooling once again took center stage. While meeting the environmental needs of the art collection was a primary goal, energy efficiency also was important to the design team. “Bowdoin College has made a commitment to sustainable design and building,” Collins says. “The college has developed its own sustainability program and requirements. They’ve got a lot of really old buildings on campus, so they have different standards for new construction and existing buildings.”
To deal with the building’s temperature challenges, the team again looked underground. “We implemented a geothermal system, so there wouldn’t be a lot of energy expended for cooling,” Ello says. “It was tricky because we were working around exquisite historic galleries. It was difficult to get all the ductwork to run in a building of that stature.”
The geothermal system consists of four, 1,500-foot- (452-m-) deep standing-column wells mated to 14, 10-ton (9.1-metric ton) heat pumps. This provides all the cooling for the building, as well as the reheat for humidification. “We’re not burning any additional fossil fuels,” Collins adds. “We’ve got no CFC-based refrigerants or anything.”
Heating for the Bowdoin College Museum of Art has always come from Bowdoin College’s central steam plant and still does today. However, because of upgrades to the building envelope and air-distribution system, the museum draws less pounds of steam per hour than it did before the renovation, despite the near doubling of the building’s square footage.
The building envelope did present its own challenges. “Certainly with no insulation and the brick mass of the exterior walls serving as the only safeguard against outside temperatures, we wanted to create a tighter building,” Ello says. “Maine winters have cold, dry air and that is juxtaposed against the warmer, more humid air inside the wall. That also creates a lot of condensation. We wanted to tighten up the overall envelope and reduce the overall heating and cooling load on the building.”
To combat temperature and moisture issues, joints were carefully sealed and new interior walls created an airtight building within a building. “We furred the new plaster wall off the brick by about 6 inches (152 mm),” Collins explains. “We turned the cavity between the plaster and brick wall into a return-air plenum. The warm, conditioned air works its way down through the room and then is drawn under the plaster wall. It washes up the wall between the plaster and brick where it is drawn into the ductwork and returned to the air-handling unit.”
This negative-air-pressure cavity was developed collectively by Machado and Silvetti Associates along with Norwalk, Conn.-based mechanical/electrical/plumbing engineers Altieri Sebor Wieber and Watertown, Mass.-based exterior enclosure consultant Simpson Gumpertz & Heger. It keeps the brick warm and dry while creating a barrier against cold and moisture. “With this solution, the masonry stays warm all the time so you never have a situation where cold masonry runs into warm, moist air, creating condensation,” Collins says. “It’s a great solution to an uninsulated masonry wall and prevents condensation that can lead to mold.”
LET THE SUN SHINE IN
The original structure was not built with daylight in mind. There were a total of 10 windows in the walls of the building. Since little could be done to change that, other ways were found to incorporate daylight. “We implemented a skylight system for the gallery spaces so visitors could get the benefits of changes in mood that daylighting affords without allowing damaging ultraviolet light into the spaces,” Ello says. “We hadto make sure we had the proper films and UV filters on the glass to control the daylight, but we wanted to make sure the spaces could benefit from natural lighting.” Clerestory windows in the below-grade areas ensure that even the subterranean galleries receive some daylight.
For Collins, landfill diversion and material reuse was a very important consideration. “In my mind, one of the most sustainable aspects of the project was reusing everything that already existed in the shell and roof of the building,” he says. “The amount of embodied energy in that structure is enormous. We’re talking about 4-foot (1.2-m) granite walls and many wythes of brick. We reused 100 percent of the shell of the building—the roof, the walls, everything.”
Storm water was another concern on the project. “All the gutter and downspout systems were feeding into a town storm-water system,” Ello explains. “The system is overtaxed and heavy rains would cause water to back up into the building. We developed a large sand and gravel infiltration bed to deal with storm water on-site and reduce the load on the town’s system. Water feeds through a series of perforated pipes and then seeps into the ground.”
The renovated Bowdoin College Museum of Art opened to an enthusiastic community on Oct. 14, 2007. Response to the delicate yet massive project has been very positive and the team behind the work is pleased with the outcome. “It was a great technical feat, but when you go through the building now it looks like historic galleries that have always been this way,” Ello says. “It makes us all proud to know it looks almost inevitable; that it came across as effortless when there was so much work behind the scenes.”
OIL COMPANIES TO CLEAN U.S. GROUNDWATER
Throughout the next 30 years, some of the nation’s largest oil companies will have to pay to clean groundwater contaminated with the gasoline additive methyl tertiary butyl ether. To settle a suit brought by 153 public water providers in 17 states, a dozen companies— including BP, London; Shell, The Hague, Netherlands; ConocoPhillips, Houston; and Chevron, San Ramon, Calif.—will have to pay a total of $423 million. Six defendants, including Exxon Mobil, Irving, Texas, did not agree to the settlement. MTBE, which had been added to gasoline since 1979, increases octane levels, is a possible carcinogen and can give water the taste and odor of turpentine. It now is banned in 23 states and oil companies stopped using it in 2006. Estimates of the cleanup cost have reached $30 billion.
Site Monitors Drought
The Drought Monitor, produced by the National Drought Mitigation Center, Lincoln, Neb.; National Weather Service’s Climate Prediction Center, Camp Springs, Md.; and U.S. Department of Agriculture, Washington, D.C., helps people and institutions develop and implement measures to reduce social vulnerability to drought. The map uses a classification system to show drought intensity and type, similar to the schemes currently in use for hurricanes and tornadoes. It combines key indices of rainfall and drought to produce the final drought intensity rating. Because drought often affects various activities differently, the map indicates whether drought is affecting agriculture, water supplies or fire danger. It is updated weekly with data from numerous sources, including the National Climatic Data Center, Asheville, N.C.; regional climate centers; USDA’s Joint Agricultural Weather Facility, Washington; and U.S. Department of Interior’s U.S. Geological Survey, Washington. View the site at drought.unl.edu/dm.
Bowdoin College Museumof Art [ Brunswick, Maine ]
[ OWNER ] BOWDOIN COLLEGE, Brunswick, Maine, www.bowdoin.edu
[ ARCHITECT ] MACHADO AND SILVETTI ASSOCIATES, Boston, www.machado-silvetti.com
[ GENERAL CONTRACTOR ] CONSIGLI CONSTRUCTION CO. INC., Portland, Maine, www.consigli.com
[ MECHANICAL ENGINEER ] ALTIERI SEBOR WIEBER LLC, Norwalk, Conn., www.altieriseborwieber.com
[ WATERPROOFING/EXTERIOR ENCLOSURE CONSULTANT ] SIMPSON GUMPERTZ & HEGER INC., Watertown, Mass., www.sgh.com
[ MECHANICAL CONTRACTOR ] JOHNSON & JORDAN INC., Scarborough, Maine, www.johnsonandjordan.net
[ BRICK ] MORIN BRICK CO., Auburn, Maine, www.morinbrick.com
[ LOW-VOC PAINT ] THE SHERWIN WILLIAMS CO., Cleveland, www.sherwin-williams.com
[ HEAT PUMPS ] CLIMATEMASTER, Oklahoma City, www.climatemaster.com
[ AIR-HANDLING UNITS ] York by JOHNSON CONTROLS, York, Pa., www.york.com
[ WINDOWS ] KAWNEER, Norcross, Ga., www.kawneer.com
[ GLASS CURTAINWALL ] Starphire low-E insulated glass from PPG INDUSTRIES CO., Pittsburgh, corporateportal.ppg.com