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A Deep Retrofit of Crown Manor
Metro Vancouver Housing Corporation (MVHC) provides safe and affordable rental homes for more than 9,000 people on 49 sites across the Metro Vancouver region. The sites are diverse, mixed-income communities that include families, seniors, and people with disabilities.
In its 10-year plan, MVHC has committed to a 25% improvement in energy efficiency on all major rehabilitations, along with a portfolio-wide GHG reduction of 45% by 2030 (relative to a 2010 baseline). The plan provides a vision and framework to guide how we will provide, preserve, and expand affordable housing in the region.
As one of the largest affordable housing providers in Metro Vancouver, we are fully aware of the affordable housing crisis facing the region. We recognize both the need to increase our housing portfolio and to keep rents affordable. A key strategy to keeping rents affordable is to minimize our capital costs. Because rehabilitating the existing building stock is less expensive than redeveloping a site, rehabilitation reduces the pressure on MVHC to increase rents. Another important goal for MVHC is to avoid relocating tenants – something that cannot be done if a site is redeveloped. We are undertaking deep retrofits for some of our buildings to achieve this goal and to nurture the industry with opportunities to grow its ability of renewing and decarbonizing a building at the same time. Balancing the renewal of existing housing with the creation of new affordable housing will require significant investment, innovation and collaboration.
Targeting Emissions in Our Portfolio
Each year MVHC conducts building benchmarking that measures energy use and greenhouse gas (GHG) intensity to determine our highest emitting buildings per square meter. This information, along with other building information, is used to determine future rehabilitation projects. By strategically targeting our most GHG-intensive buildings, MVHC is on track to meet its aggressive 2030 target.
As of 2022, Crown Manor was the fifth most GHG-intensive building in the MVHC portfolio. It is a 29-unit, affordable rental housing site in New Westminster that consists of a four-level apartment building with a penthouse unit on the roof. A portion of the ground floor is dedicated to surface parking which extends out towards the service lane behind the building. It was built in in 1966, making it one of the oldest buildings in MVHC’s portfolio.
This housing site was one of three MVHC sites involved in the Pembina Institute’s Reframed Initiative which began in 2021. The Reframed Initiative is a multi-partner initiative to demonstrate the technical and economic feasibility of whole-building retrofit solutions that integrate energy efficiency, decarbonization, seismic safety, and climate adaptation on existing multi-unit residential buildings (MURBs). Although accessibility was included in the list of the Reframed objectives, it is difficult to increase the number of accessible units while keeping tenants in-place. This is because improving accessibility includes interior renovations which require a tenant to vacate their unit. For this reason, and to reduce costs, accessibility improvements within the units were excluded from MVHC’s objectives.
When selecting buildings for Reframed, MVHC chose three of our most energy and/or GHG-intensive sites. Other considerations for inclusion in Reframed included the age and condition of the building.
The Reframed Revelation
Phase A of Reframed included six consulting teams that took part in six different workshops with various subject matter experts to create four schematic designs and one final concept design for each of the six MURBS in the initiative.
The four schematic designs, or retrofit bundles, that Williams Engineering presented to MVHC for Crown Manor were generally the same except for the level of building envelope upgrades and space heating upgrades. Each bundle was evaluated against different project objectives and assigned a rating from 1 to 4, with 4 being the best rating. Each project objective was assigned a weighting, allowing Williams Engineering to calculate a score for each bundle.
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Based on the weighted average, Bundle 2 was the preferred option of the consulting team. This bundle included:
- Replacement of a portion of the building envelope with new wall components (plywood sheathing, continuous air/moisture barrier, exterior insulation and cladding),
- New low-slope roofing with additional insulation,
- New fibreglass-framed or vinyl-framed windows and sliding doors,
- New balcony membranes and fascia-mounted guardrails
- New high efficiency, electric HVAC equipment including air source heat pumps (ASHP) to heat domestic hot water, PTAC units for in-suite cooling, rooftop ASHPs for tempered ventilation of common areas,
- Addition of shear walls (and associated grade beams) inside the building to improve seismic resilience,
- Increase in liveable floor area (9%) by adding two new one-bedroom units at the ground level,
- Addition of an exterior ramp to the main entrance to improve accessibility.
The addition of two ground-level units would increase the affordable housing supply and MVHC’s revenue.
MVHC decided to proceed with a modified Bundle 2 that included the replacement of the existing condensing gas boiler (for centralized space heating) with an electric ASHP. We will retain the existing boiler as a backup unit as it’s not at the end of its service life. With this modification, the bundle reduced our energy use and GHG emissions by 62% and 98% respectively (compared to the existing building). The GHG emissions are based on a switchover temperature of -10 C for the ASHP. The total construction cost for this modified Bundle 2 was just over $3.7M, including an upgrade to the main electrical service to the building. Adding the electric ASHP for space heating resulted in a minor capital cost increase of approximately $50K.
Travelling Through the Procurement Portal
After the Pembina initiative was completed and we had settled on a modified bundle of retrofit measures that met MVHC’s objectives, we secured approval and funding to proceed with the project. MVHC’s procurement policies required a public Request for Proposals process to take the project from schematic design to detailed design. This significantly increased the duration of the design phase and increased the risk that the detailed design would deviate significantly from the schematic design. Although the design team selected for the detailed design phase is not the same one that developed the schematic design, it appears that the detailed design will follow the design intent proposed during the schematic design phase.
Written by Ross Arbo, Metro Vancouver Housing Corporation
