By Andrew Peel
The Raymond Desmarais Manor tower (the Manor) at 255 Riverside Drive East in Windsor, Ontario, is undergoing a rare transformation in North America: a stepwise retrofit of a tall multifamily building to the EnerPHit standard.
The owner, Windsor Essex Community Housing Corporation (CHC), spends an incredible half of its operating budget on energy, much of which is consumed by electrically provided space heating. Being a social housing organization, CHC sees providing affordability and occupant comfort as key factors in its decision-making process, so it looks for ways to reduce the occupants’ energy costs. While winter weather creates comfort issues, so do summer conditions. The hot and humid weather experienced in Windsor during peak summer poses challenges to passive cooling strategies. Many existing towers in the region do not include active cooling. The consequences are either the installation of low-efficiency window or through-wall air-conditioning units, or residents must endure uncomfortable—and potentially unhealthy—conditions.
The Manor is not the only tower attempting to achieve the EnerPHit standard. Another project, the Ken Soble Tower retrofit down the long road in Hamilton, Ontario, is also pursuing EnerPHit. However, there are three characteristics that make the Manor unique:
The first is tenancy during construction. Whereas the Ken Soble Tower has been vacant for some time, the Manor is occupied and remains so during construction work. This is problematic for a variety of reasons, including that the HVAC installation in corridors and suites will disrupt tenants and testing the airtightness of the whole building becomes much more complicated.
The second is the existing balconies. The Ken Soble Tower renovation includes removing the balconies. At the Manor, they are being kept per client request, as the tenants use them regularly.
The third is the stepwise approach. Funding constraints made it impossible for CHC to implement all the required works in a single phase.
Standing 20 stories high, the 300-unit tower was built in 1974 as part of the government’s massive build-out of affordable apartment buildings. The existing building has a concrete structure and an exterior wall construction consisting of through-the-wall brick masonry, 1.5‑inch interior EPS insulation, and parging. The parged brick wall acts as the air-and-vapor control layer. Three inches of roof insulation was added as part of a roof upgrade over a decade ago. Windows are original aluminum frame with single-pane glazing. The HVAC system comprises a gas-fired makeup air unit pressurizing the corridors, local exhaust fans in the kitchen and bathroom, and electric baseboard heaters below the patio doors and living room windows. New gas boilers for domestic hot water (DHW) were installed about ten years ago, although the circulation piping is original and due for replacement. The elevators are also due for upgrades.