By Emma Norton, Nick Rudnicki and Lorrie Rand
Nova Scotia has committed to aggressive reductions in greenhouse gas emissions, targeting a 53% reduction below 1990 levels by 2030, and net zero emissions by 2050. A recent report by Brendan Haley and Ralph Torrie states that existing buildings are responsible for 47% of Nova Scotia’s GHG emissions. Read more …
In 2030, more than 75% of the building stock in Nova Scotia will be composed of buildings in use today, and an estimated 60% of those buildings will still be in use in 2050. This means that existing buildings will have a large impact on meeting Nova Scotia’s emissions targets.
In light of these facts, the ReCover Initiative was established to develop a Deep Retrofit methodology for Nova Scotia that can be implemented at a large scale.
Our goal was to achieve enough energy savings to ensure that the building could be net-zero with the addition of renewables. As such our approach involved energy savings through superinsulation AND an airtightness target of 1 ACH (passive house retrofit target), fuel switching of the building mechanicals (from fuel oil to electric), and addition of high-efficiency new equipment, including dedicated ERVs in each unit and then solar PV.. Essentially the pathway is to conserve as much energy as possible, to electrify everything, and then to offset the small amount of energy needed with renewables.
Our team performed a pilot design, with the support of Quest Canada and the Nova Scotia Department of Energy and Mines, to demonstrate the potential reductions in energy consumption and GHG emissions that could be achieved by applying this methodology to the retrofit of a low-rise MURB (multi-unit residential building) pilot building in Halifax.
Conventional methods of performing deep energy retrofits are slow and expensive, because every project is custom, as every building is unique. The ReCover Initiative is based on a systematic, turnkey approach to affordable deep energy retrofits, developed in the Netherlands, called Energiesprong (“energy leap”).
The ReCover process involves wrapping the building in a new prefabricated skin and replacing the mechanical systems with smaller, more efficient components. This work is faster and less disruptive than a typical renovation, and it allows for occupants to remain in their homes throughout the work. Additionally, following a proven, systematic process reduces risk to the contractor and reduces costs to the owner.
Emma Norton is with QUEST Canada; Nick Rudnicki is CEO RSI Projects and a Passive House-trained builder; and Lorrie Rand is president of Habit Studio and a Certified Passive House Designer.
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