The Shaw House renovation project had four major objectives:
- To provide supportive housing for our elders.
- To build responsibly and in a sustainable fashion, thereby improving air quality.
- To intensify land use and increase urban diversity.
- To respect historical building typologies that the community deems to have been culturally effective.
The Shaw House, officially opened in 2003, is a renovation of and addition to an existing dwelling on Toronto Island. Sponsored by the Toronto Atmospheric Fund, whose objective is to reduce Toronto’s greenhouse gas emissions, the aim of this particular renovation project was to demonstrate how CO2 emissions can be reduced by responding to site conditions, reuse of the existing dwelling and employing sustainable building methods and materials.
The building sits on the periphery of the Toronto Island residential community and is owned by the Toronto Island Residential Community Trust. It was conceived to address the aging demographics of the community, keeping seniors in their own neighbourhood, in a building that offers a high level of comfort and control combined with low maintenance and operating costs, without compromising the needs and aspirations of future generations. To achieve this the existing building is “turned” towards the sun by adding to the south elevation on the ground floor and taking away from the roof mass on the second floor. The north elevation respects the community and retains traditional architectural vocabulary with dramatically increased levels of insulation. The enlargement and conversion of a single-family dwelling into a multi-unit residence intensifies land use.
There are four units, two on the main floor, two on the second, and each is directly accessible from the outside and acoustically separated from the next. Grade access is provided to all units to accommodate wheeled access (bundle buggies, bicycle carts, wheelchairs, etc.) as there are no cars on the island. The ground floor houses shared laundry facilities. All units have large windows that open outward and upwards maximizing the garden views, which each resident can enjoy.
The ground floor also contains a 750-square-foot community space featuring coffered ceilings, wood paneled walls, orange-pink fir floors and a large hearth containing a gas fireplace. This is the main part of the original building, and is available for rent by the public as well as for the community; it opens up onto two patio areas and the large garden.
The downstairs residential units are accommodated on the southwest elevation, with the addition of small radial bays, effectively turning the building towards the sun and away from the winter winds. Adjacent to each unit is a “front porch,” which is oriented to capture the prevailing summer breezes off the lake. Each porch has a generous cantilevered roof and suspended trellis to filter light entering the living space. An organic sod roof is applied over the ground floor addition. The vegetative cover extends over time to become entwined with the metal lattice of the suspended trellis. The leafy deciduous planting provides critical protection at appropriate times of the year as the annual growth and loss of leaves is in sync with the cycles of heating and cooling for the building.
The second floor has two self-contained units. Each second floor unit has access to private outdoor spaces, which are created by cutting voids out of the large pitched roof exposing the living spaces to the sun and prevailing summer breezes.
The Shaw House is an ambitious project involving the adaptive reuse of an existing structure to provide accommodation for seniors. This is accomplished by expanding upon the now well-established attitude of protecting the environment to include actively improving environmental conditions including reducing CO2 emissions.
A. Site conservation
The design approach seeks to adopt and recycle all on-site resources, maintaining the existing structure in its relationship to the garden, and to add to the existing elements to maximize sun exposure. All native vegetation is preserved and pruned resulting in a somewhat random and unpredictable site plan, which is indicative of the adjacent park encroaching on the dwelling. Trees, particularly older growth are major stores for CO2. The portion of the garden which is occupied by the building addition is recovered in the form of a roof garden.
B. Building form and orientation
The building was originally constructed to be parallel to the street grid with little regard for the natural environment. In this scheme, the original footprint of the house is maintained and radial additions with large expanses of glass are added to take advantage of passive solar heating and the prevailing summer breezes. On the second floor large voids are cut out of the roof to achieve the same effect. Suspended metal trellises are used to protect from overheating in the summer. A heavily insulated curved wall protects from winter winds.
C. Energy conservation
Abundant insulation, natural cross ventilation, solar heating and evaporative cooling will ensure heating costs will be minimal and air condition not required. Thermal mass is incorporated through the use of slab on grade concrete on the ground floor and light weight gypsum on the 2nd floor units. In floor hydronic heating is used to distribute the heat throughout the building. Triple glazed, fiberglass framed windows ensure the highest possible thermal performance.
D. Water conservation
The sod roof, while enhancing bio diversity has the added advantage of retaining storm water, restoring oxygen to the atmosphere, and providing natural cooling through evaporation. An abandoned cistern under the house will be modified to store excessive rainwater for use in the garden. Low flow fixtures are specified and a gray water management system will be installed pending city approval.
- Footings: 30% rubble concrete
- Foundation wall forms: wood particle concrete, 78% recycled (Durisol block)
- Straw bale walls
- Wood siding: Existing reused
- Windows: Triple glazed, low E Argon in fiberglass frames (Inline Fiberglass)
- Insulation: Recycled slag (Roxul)
- Alpine roof: Rubberized asphalt (Hydrotec) or two ply modified asphalt (Soprema)
- Metal Roof: Zinc (Rhinezink)
- Wood trim and cabinetry: recycled sawdust (Medite)
- Solar panels integrated between standing seams of roof
F. Other factors
The introduction of straw bale construction demonstrates many of the principles, which the dwelling attempts to communicate. By using local materials in an innovative fashion transportation costs are reduced, dependence on highly manufactured goods and specialized labor is reduced and all materials used in the fabrication are readily recyclable.