50 Forward: Sustainability
Sustainability has always been an integral part of our design culture. From a passive design for a Boston police station in the ’70s to early natural lighting efforts at Martha’s Vineyard High School in 1980, and an ice thermal energy storage system at the Tyngsborough High School in 1991, we continue move our practice and our commitment to climate action forward as we look to the next 50 years. And today more than ever, clients are concerned about climate change and see their building project as an opportunity to make a difference.
We actively seek ways to create sustainable, resilient buildings and campuses with reduced carbon footprints. This means offering our clients the best options in energy efficiency, renewable energy sources, healthy materials, and the reduction of water use and waste.
A Fossil Fuel Free Future
The existing Arlington High School is an iconic building, beloved by the community. From the initial planning, the community wanted the new high school design to respect the past and remain iconic into the future. One of the ways they hope to achieve that is by creating a fossil fuel free school that embodies and showcases the town’s commitment to environmental sustainability. The only fossil fuel emissions generated will be offsite at the utility plants. Emissions are further reduced through robust energy efficiency measures, solar electricity produced on site, and any renewable energy purchased by the Town.
Designed for 1,755 students, the new High School will be a large complex that includes a daycare center, School District administration and special education Preschool and LABBB collaborative all on a tight urban site. The strategy for eliminating site-based fossil fuel consumption began early in design. First, we worked to get the building footprint as efficient as possible. Next, we designed a thermally efficient building envelope. The more efficient the building envelope is, the more the heating and cooling load is reduced. But efficiency, while a critical goal, does not eliminate carbon use. That requires heating and cooling with renewable energy sources. Arlington’s goal is to use ground source heat pumps with 130 geothermal wells located in the athletic fields and under parking to eliminate the need for natural gas (a fossil fuel) to heat and cool the building.
All lighting and equipment within the school, from the science labs to the kitchen, are electric. The school will eventually have more than a megawatt of solar photovoltaic collection. The roof of the building has been designed and structured for enough PV to power 30% of the school. When the building opens, the town plans to purchase carbon offsets, and, over time, install more photovoltaics until fossil fuel free operation is achieved.
Protecting Our Limited Resources
In designing the new 271,000-SF Saugus Middle/High School, which will open in 2020, the school administration was inspired by their own Saugus River. Through sustainability charrettes and our design process, a high priority was placed on reducing water use as much as possible. Limiting water use starts at the top; that is, the top of the building. The building’s green roof will absorb water for maintaining the plantings located in rooftop planters that serve as an educational tool. Students will grow varieties of vegetation based on curriculum, while the extensive green roof will provide evaporative cooling, slow the rate of stormwater run-off, protect the roofing membrane from UV damage and thermal stresses, provide some addition wildlife habitat for birds and insects, and be an aesthetic amenity for the building.
The water that lands on the roof and is not absorbed goes into rain leaders that carry the water to three 30,000 gallon underground cisterns. The water collected in one cistern is used for flushing all of the toilets in the building. In schools, where most water use is for toilet flushing, and can amount to 20 gallons per student per day, reusing rain water can be a major water conservation measure. The other two cisterns are used for irrigating the planted areas immediately adjacent to the building and the natural turf at the athletic field. The rest of the campus relies on drought resistant plantings and is not irrigated.
We did not stop there. Rooftop cooling units constantly drip condensate when they run in the summer, which is typically the season with less rainfall. We are looking at ways to collect and reuse the condensate from rooftop units, which will reduce water use even further.
While water use was a high priority, we also looked at how the school impacts the environment around it. There are rain gardens integrated into to the parking lot that slow and filter stormwater before it runs into the storm water system. This helps protect the surrounding resources from the oily run-off from cars and slows the flow which allows water to penetrate the soils more deeply and reduces the size and cost of installing underground stormwater detention systems.
Bristol County Agricultural High School is a learning lab for the community. The school’s environmental ethic is a key element of the curriculum and is reflected in how we approached the design of the campus. The project will be designed for energy efficiency and sustainability with green roofs, rainwater collection, alternative structural materials, and photovoltaics. Those are what we might call the flashy sustainability efforts and will allow students to learn about their environment.
Some of the subtler elements that also make the project a teaching tool include the materials within the building. We researched our material selections to incorporate low-carbon, recycled, local and healthy materials wherever possible. For instance, linoleum flooring was used instead of vinyl. Linoleum is primarily made from rapidly renewable linseed oil and jute, and renewable wood flour and can be cleaned with water. Vinyl is petroleum based and needs to be cleaned with detergents which is both an environmental and maintenance issue. The wood and heavy timber structure for three of the six new buildings at Bristol Aggie is primarily FSC-certified ensuring environmentally conscious forestry practices that protect the future of our forests. Wood stores carbon for the life of its use and in production, releases less carbon than steel or concrete.
Many small design decisions at Bristol Aggie make a difference in environmental sensitivity and resource management, but perhaps some of the most important are those that contribute to the health of the occupants. We have purposefully incorporated finishes such as paints, adhesives, and fabrics with low or no VOCs. These choices provide a healthier interior environment and are proven to have an impact on cognition. We make smart material choices by coordinating standard shapes of products to reduce field cutting and waste. We use durable materials like brick, stone, or metal roofs, which can last three times as long as asphalt shingles. Stone is locally sourced to reduce transportation impacts. Durable building design delays the need to build again, which ultimately is the best way to reduce energy and carbon impact.
We know reducing energy use, reducing water consumption, increasing our use of renewable energy sources and smart materials will play into sustainability for a long time to come. In looking at our next 50 years, we are designing buildings with smaller environmental impacts. This will assure healthier students, resilient and sustainable communities, and a more viable future for all of us.