Guidance on upper indoor temperature limits: Protecting the health of older adults - Canada.ca

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

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(752 KB, 36 pages)

June 2026

Table of contents

1.0 Executive summary

2.0 Introduction

2.1 Purpose

2.2 Intended audience

3.0 Background

4.0 Evidence review

4.1 Limitations of current evidence

4.2 Summary

5.0 Recommendation: Indoor temperature limit based on evidence and health risk for older adults

6.0 Resources

7.0 Acknowledgements

8.0 References

Appendix A: Summary of evidence

A1.0 Overview of rapid literature review methodology

A2.0 Thermal safety versus thermal comfort

A3.0 Descriptions of supporting evidence

A4.0 Moving forward

Appendix B: Policies, regulations, standards and guidance

1.0 Executive summary

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.

2.0 Introduction

Recent evidence from Environment and Climate Change Canada shows that Canada is warming at over twice the global average, with northern regions warming at nearly three times the global meanFootnote 1Footnote 2. With the rapid increases in global temperatures, and with Canada warming at a higher rate compared with the rest of the world, actions aimed at protecting people living in Canada from the health impacts of climate change are becoming increasingly important.

In recent years, Canada has experienced extreme heat events, most notably in Quebec in 2018Footnote 3 and in British Columbia in 2009Footnote 4 and 2021Footnote 5, resulting in the deaths of hundreds of people, the majority of whom died indoors. For instance, during the 2021 British Columbia heat event, 98% of heat-related deaths occurred indoors, and most victims were over 60. More specifically, 67% of decedents were 70 years and older and 90% were 60 and older, closely mirroring provincial mortality rates of 70% and 85% for these age groupsFootnote 6. Globally, heat attributable excess mortality in this demographic has increased 81% from the 2000 to 2005 average, reaching a record 345,000 deaths in 2019Footnote 7.

Currently, provincial and national building codes, except in British ColumbiaFootnote 8, do not require maintaining upper indoor temperature limits. Active cooling systems are also not universally available. In 2023, Statistics Canada reported that on average, 77% of Canadian households had at least one type of air conditioner; of these (with significant variation by province), 41% of Canadian homes had central air conditioning, and 20% had stand-alone units (for example, window-mounted air conditioner)Footnote 9. In Canada, extreme heat events have increasedFootnote 10 and are projected to become more frequent, more intense and of longer durationFootnote 11. Protecting populations at greater risk, such as older adults, from heat stress is critical for reducing the growing health burden.

Since 1998, Health Canada has worked with provincial and territorial partners to address the health impacts of climate change, including extreme heatFootnote 2Footnote 12. Following the 2003 European heatwave, where 72,000 deaths were recordedFootnote 13, Canada prioritized...