Most of the Greater Toronto Area's rental apartments were built before 1980, and many still rely on aging heating and cooling systems. Modernizing these systems can lower energy use and operating costs, improve resident comfort, and reduce the risk of costly breakdowns.
How old is Ontario's rental housing stock?
According to the Urbanation-FRPO Ontario Rental Market Study Update (March 2025), Ontario's purpose-built rental apartment universe reached 707,853 units in 2024, and approximately 87% of Greater Toronto Area rental stock was built before 1980. Many of these buildings still operate heating and cooling equipment that is decades old, and in many cases systems have been repaired again and again rather than replaced.
That matters because heating and cooling is one of the largest energy uses in an apartment building, and one of the systems residents notice most. When it underperforms, owners feel it in utility bills, service calls and tenant complaints.
What are the risks of aging HVAC systems?
Higher energy consumption and utility costs as older equipment loses efficiency
More frequent breakdowns and emergency repairs, often during the coldest or hottest weeks of the year
Uneven heating and cooling, leading to resident comfort complaints
Replacement parts that become harder to source for older equipment
Greater difficulty meeting evolving efficiency standards and regulations
Emergency replacements also tend to cost more than planned ones, because owners have less time to compare options, schedule the work or apply for available incentives.
What does HVAC modernization involve?
Modernization is usually phased rather than done all at once. A typical approach includes four steps:
Assessment: review the age, condition and performance of existing equipment and controls.
Equipment upgrades: replace older boilers, chillers and ventilation units with high-efficiency systems sized for the building.
Building automation: add controls that schedule, monitor and adjust heating and cooling based on demand.
Preventive maintenance: put a planned service program in place to keep new equipment running efficiently.
Available energy-efficiency rebates can help offset part of the upgrade cost, so it pays to review incentive programs before equipment is selected. Owners should also confirm program requirements early, since some incentives must be approved before work begins.
Where should building owners start?
Most owners start with the equipment that is oldest, least efficient or most likely to fail, then build a multi-year plan for the rest of the building. Pairing upgrades with a long-term maintenance agreement helps protect the investment and makes operating costs more predictable. An assessment also gives owners the information they need to compare options, set a realistic budget and plan work around residents, such as scheduling heating upgrades outside the winter season.
Key takeaways
About 87% of GTA rental buildings were built before 1980.
Aging HVAC equipment raises operating costs and the risk of failure.
A phased plan of assessment, efficient equipment, automation and maintenance delivers the best results.
Kontrol Technologies helps owners and property managers of commercial and multi-residential buildings plan and deliver heating and cooling upgrades. Contact us to discuss your building.