Bois Ellen Cooperative Housing, Laval

The Bois Ellen coop represents an accumulation of knowledge, experience, and lessons learned from both Rosemont and Benny Farm: building envelope and technical measures on the one hand, and community involvement and empowerment on the other. Bois Ellen was designed for seniors and families, while simplifying ongoing maintenance for the client and inhabitants. Being in the suburbs rather than downtown, one of the challenges was to develop high-quality public space. The core innovation at Bois Ellen was a significant upgrade in many energy and building envelope innovations: the “TOWARDS PASSIVEHOUSE” approach to the design.


The next innovation: towards Passive Solar Design

Over the last five years, we designed the “Bois Ellen Cooperative Residence” (Bois Ellen for short) as a TOWARDS PASSIVEHOUSE building, in joint venture with Giasson Farregut Architects. The buildings include major innovations in the building envelope, as well as energy efficiency, thermal comfort, and interior air quality that is rarely if ever seen at this scale for affordable housing. In addition, we again respected the capital “pilot project” budget limitations, which were less than ten percent above the conventional social housing budget in Quebec.

Many of the building science recommendations and technical innovations emerged from the collective experience of the expert consultants, client and others involved in the IDP and were applied to the following three areas of focus:

  1. Improvements to the building envelope—essential to the long-term energy efficiency of a building.
  1. Improvements to building systems—including heating, ventilation and air conditioning (HVAC), plumbing and electrical systems—important to overall building performance.
  1. Implementation of effective mechanisms of coordination— testing and performance monitoring during the construction phase and during a year-long monitoring phase necessary to provide feedback on the success of the measures included in the building.


The Context

The project is in the city of Laval, Quebec, located immediately north of the Island of Montreal, in a primarily industrial neighbourhood. The L-shaped building is located on the site of an old lumberyard (hence the name Bois Ellen) on rue Robert-Élie, a stone’s throw from the Boulevards du Souvenir and Concorde and the Montmorency metro station and Concorde train station. Although not located in a dense urban setting like downtown Montreal, Bois Ellen’s location is interesting in that the City of Laval had recently changed the zoning after developing the Concorde train station in order to encourage Transit-Oriented Development (TOD), meaning greater density and mixed-use development. Robert-Elie street has also been redesigned for a bike lane to connect to public transit, and the City is also planning to shorten the distance between Bois Ellen and the metro station (since a viaduct is currently creating a circuitous route by foot or bike to the metro) by putting in a new path and pedestrian bridge over the train tracks.

The thirteen-storey residential tower is designed for both independent but less-mobile seniors and families, and these two user groups are able to interact in the building’s interior courtyard, which is located on top of the interior parking. Since the City of Laval mandates 60% of parking to be indoors, we took this opportunity to create a meeting space.

Bois Ellen was financed in part by the Société d’Habitation du Québec’s Projet Innovation, a program that offers 10% additional funds for social housing projects that demonstrate a commitment to energy efficiency and environmental strategies – something that was important to the client from day 1.


The Integrated Design Process: More emphasis on the professional team

Although there was relatively modest client representation present throughout the design process (compared with Rosemont and Benny Farm), the client representatives clearly expressed their preference for a building that is easy to maintain and pleasant to inhabit without requiring the same amount of involvement as in Rosemont and Benny Farm. However, since our energy and comfort goals were higher than in Rosemont and Benny Farm, we knew that a robust integrated design process would be needed with the carefully selected professional team.

As with Benny Farm and Rosemont, the Bois Ellen project started with a charrette that encouraged ongoing inter-disciplinary collaboration among the project team members. One of the innovations that everyone agreed upon from this first charrette was to keep things as simple as possible above all else. This client could handle little hands-on maintenance of complex systems.

Part of the process involved a whole-building-analysis and energy-simulation approach developed by Enersys Analytics Inc. It was adopted even before the first design charrette as a useful way to understand and forecast the complex performance issues over multiple timelines for the proposed building design.


Environmental Systems and Transferability

Building on the lessons learned from Benny Farm and Rosemont, the project team strategically identified the most appropriate sustainable innovations that respected the modest budget while envisioning an even more modest time investment on the part of the cooperative and its board members in terms of ongoing maintenance. The Bois Ellen project emphasizes the use of passive means to achieve energy efficiency and thermal comfort. The final built project should give better energy efficiency than Rosemont and is expected to have better and more even thermal comfort, even though the building structure (concrete) is much more difficult to build while reducing thermal bridges.

Bois Ellen is an energy-efficient, robust, and cost-effective building design requiring little maintenance. The higher initial investment in high-performance windows and doors give significant energy savings – a key component of the passive design strategy. Bois Ellen integrates the durable and resilient installation of systems and products that reduce the risks associated with premature building decay and dysfunction. It incorporates building systems, products, and installations that improve the comfort and quality of the interior environment. And finally, Bois Ellen balances individual unit energy saving measures, whereby residents’ living habits directly affect their energy bills, with efficient centralized building energy measures, whereby individual maintenance responsibilities are kept to an absolute minimum – all for a mere $119/sf.