The effective thermal performance and air tightness of a building enclosure is fundamental to the selection and operation of HVAC systems to control interior conditions. An enclosure that effectively addresses thermal bridging and air leakage can significantly improve the predictability of loads and reduce peaking on building HVAC systems. In turn, systems can be optimized to improve performance and energy efficiency. This paper will provide the findings of a research project at a 13 storey multi-unit residential building in Vancouver, BC that is currently underway to better understand how comprehensive building enclosure energy efficiency upgrades affect the performance of building HVAC systems by providing analysis of monitoring and testing data.

Renewal work to the building enclosure has been undertaken, including energy efficiency upgrades. These upgrades include the addition of continuous exterior insulation over the entire exterior façade of the building, use of thermally efficient fiberglass cladding support clips, new over-cladding, replacement of the existing windows with triple-glazed fiberglass high-performance units, and improved air barrier sealing.

Data collection includes a combination of airtightness testing, multipoint tracer testing, make-up air unit intake and corridor supply flow measurements, continuous monitoring of interior conditions throughout the building, monitoring of exterior environmental data, and monitoring of energy consumption on a suite by suite basis. These data are used to quantify the operational behavior of the building and its HVAC systems. This paper examines the impact of the building renewal on the energy consumption of the building and the ability of the corridor pressurization systems to provide appropriate ventilation. Future research will evaluate a range of potential ventilation system upgrades in the form of in-suite HRVs.