Guidance on upper indoor temperature limits: Protecting the health of older adults

Climate change is reshaping Canada's health landscape. Rising temperatures and more frequent heat events pose serious health risks, particularly for especially susceptible populations such as older adults.

Health Canada recommends an upper indoor temperature limit of 26°C to protect older adults, defined in this document as those aged 60 and over, from heat-related illness and death. This threshold is based on a rapid evidence review of available epidemiological studies and controlled exposure research, and aligns with World Health Organization guidance and policies in several Canadian jurisdictions. Research indicates that indoor temperatures above 26°C increase physiological strain and risk of heat-related illnesses; sustained exposure to indoor temperatures between 26°C and 31°C, especially overnight, should be avoided whenever possible. While focused on older adults, these measures may also support broader population health during heat events.

This guidance is intended for public health officials and stakeholders to inform policies and interventions. It emphasizes health protection rather than comfort and acknowledges that 26°C may not fully safeguard individuals with severe frailty or multiple health conditions. Examples of possible actions that could be considered when implementing this guidance include proactive heat safety planning, discussion of personal cooling strategies, and flexible accommodations for those needing cooler conditions. This list of actions is for illustrative purposes and is not intended to be exhaustive or prescriptive.

As climate change accelerates and Canada's aging population grows, implementing indoor temperature limits is critical to reducing preventable heat-related health risks. Health Canada will continue to encourage research and policy development to protect susceptible populations.