| Résumé | Heritage buildings play a significant role in the Canadian government building stock; it is estimated that there are 1272 recognized federal heritage designated buildings in Canada, with 280 of these being classified as Federal Heritage Buildings. The majority of these heritage buildings are unlikely to have a building envelope which meets the thermal requirements of modern construction codes.
The Government of Canada, through the Greening Government Strategy, has introduced increasingly ambitious greenhouse gas (GHG) emissions reduction targets for its real property portfolio. Introduced in 2017 and updated in 2020, the Greening Government Strategy commits the Government of Canada to reducing GHG emissions by 40% below 2005 levels by 2025, and by at least 90% below 2005 levels by 2050 (Government of Canada, 2021). Departments are expected to ensure that all major building retrofits, including heritage rehabilitation projects, prioritize GHG emission reduction and resiliency to climate change.
For heritage buildings where the unique architectural features of the façade are to be conserved, achieving these ambitious GHG reduction requirements, as well as meeting modern thermal comfort requirements for building occupants, typically implies that insulation is required to be added to the interior of roofs, foundations and walls. However, it has been widely identified that for a heritage building, the addition of insulation on the interior of the building risks the exterior layers to be colder and wetter during the winter season. This can increase the risk to freeze thaw damage of heritage components in the envelope, thereby potentially risking the long term durability to heritage defining characteristics of the building. |
|---|
