dEVENS ZERO-NET ENERGY AFFORDABLE HOUSING - multi family
In response to a Request for Proposals from the Massachusetts Development Finance Agency (Mass Development), WDADG was part of a design team that developed proposals for moderately priced homes on two sites located within the Devens Regional Enterprise Zone. The project provides a replicable example of current and innovative sustainable building practices that are practical for Massachusetts homes. In keeping with the Governor’s stated goal of moving toward zero net energy development in the Commonwealth, a main goal of this project is to provide a forum for development of zero net energy, or near zero net energy, moderately-priced housing.
For the multi-family development proposal at Bates Street, the site plan builds on the pattern language and density of the existing neighborhood, maximizing solar exposure while appropriately responding to the site’s context and minimizing costs associated with building construction and realignment of the existing utility corridor. The buildings are arranged around a central open space that connects all the units, creating a distinct sense of place and a visual and physical connection to the preserved open space directly to the east.
WDADG aligned the units, set in groups of three, to give them appropriate presence on Bates and Cavite Streets. In an effort to limit pavement and maximize open space, two townhouse types were designed- one with a garage underneath. These units, along Cavite Street, have vehicular access in the form of individual driveways and a “traditional” front yard transition. The units to the north have vehicular access from the repositioned service road that now connects directly to Bates Street. These units have “front” doors on the open space and rear doors off their parking. Along Bates Street, WDADG maintained the street’s existing setback line at the western side of both north and south units to create a consistent building edge along the roadway. Combined with a continuation of the sidewalk and the introduction of additional street trees, the Bates Street streetscape maintains the consistency of materials and scale that were sought by the Commonwealth.
At Bates Street, the unit density requires an even closer relationship between the proposed stormwater management system and vegetative infrastructure. Vegetated bioswales and stormwater gardens surround all of the building units, again serving programmatic and aesthetic functions. Also, the Bates Street Service Road that previously bisected the site has been repositioned, and in its place are densely planted stormwater gardens that create vertical transition between the unit clusters and act as “ecological infill.”
To minimize stormwater runoff to the vegetated swales and maximize the site’s ability to capture stormwater runoff in-situ, WDADG designed the entirety of the vehicular and pedestrian circulation systems with different types of porous pavement. WDADG believed that varying the types of porous pavement for different uses and microclimates would allow us to attain a critical element of the goal of the project- to create a “laboratory” of sustainable materials, testing them in different types of situations and different microclimates to determine which materials work best for a given situation. To this end, all of the vehicular circulation areas (including the repositioned service road and the driveways off Cavite Street) within the site have been developed with permeable pavers, as they would receive the heaviest vehicular traffic. For the parking spaces to the north of the site adjacent to the northern units, grasscrete pavers have been introduced. These parking spaces may receive more shade than the rest of the vehicular areas during the winter months, so a paver that may better resist frost heaving has been specified. Evergreen trees are located along the northwest corner of the property to help reduce the effects of winter winds. All of the pedestrian circulation system also utilizes permeable materials such as stone dust or crushed brick, which allow for stormwater infiltration yet are still ADA compliant surfaces.
The central open space at Bates Street is unprogrammed and acts as the central unifying element of the community. All of the units face out onto the open space, creating a direct dialogue between living space and community space. Porches and small rain gardens provide transition between these private and public spaces, with rain gardens simultaneously serving as part of the stormwater management infrastructure. This open space is positioned to maximize solar access for the units, while also maintaining near maximum solar access for the central lawn. The strong east west connection, reinforced with vegetation, also affords views to the large dedicated open space to the east from Bates Street. Finally, deciduous canopy vegetation is used here as a shading device as well as a scale transition and vertical edge between the housing units and the open space.