This article describes heating equipment characteristics based on publicly available technical data. Installation of gas appliances must be completed by a licensed technician. Check local municipal codes and manufacturer clearance requirements before placing any heater near structures or combustible materials.
Canadian winters impose real constraints on outdoor heating. Temperatures across most of the country's population centres — Toronto, Ottawa, Calgary, Edmonton, Winnipeg — regularly drop below -10°C from December through February. At those temperatures, consumer-grade patio heaters designed for temperate climates underperform significantly. Selecting the right heating type and understanding its limitations is the starting point for extending outdoor use into the colder months.
Propane mushroom heaters
The tall, mushroom-cap propane heater is the most widely used outdoor heating format in Canada. Standard commercial units produce between 40,000 and 48,000 BTU/h. At ambient temperatures above -5°C, a single unit can maintain a comfortable zone of approximately 2.5 to 3 metres in diameter. Below that threshold, effective radius shrinks noticeably.
The primary limitation is propane pressure. Standard propane tanks contain liquid propane that must vaporize before combustion. Below approximately -42°C, propane ceases to vaporize — but in practical terms, performance degrades noticeably below -15°C because tank pressure drops. Some manufacturers rate their heaters down to -20°C, but output at that temperature is materially lower than rated BTU figures, which are measured at 21°C.
Practical notes
- Keep tanks in a sheltered but ventilated location when not in use; repeated freeze-thaw cycles can affect regulator performance.
- Wind reduces effective range sharply. Even a 15 km/h wind can cut the usable heat zone by 40%.
- A 20 lb propane tank lasts approximately 8–10 hours at full output on a 40,000 BTU heater.
Natural gas patio heaters
For patios with an existing natural gas line, a fixed natural gas heater eliminates the tank-pressure and refill concerns of propane units. Output ranges from 30,000 to 50,000 BTU/h depending on model. Because natural gas is delivered at consistent pipeline pressure, cold weather does not affect fuel supply or burner output in the way it does propane.
The limitation is installation cost and rigidity. Running a gas line to an outdoor pad involves permitting, trenching, and licensed gas fitting work. Costs vary considerably by municipality and existing infrastructure, but $800–$2,500 for a basic outdoor gas line extension is a reasonable planning estimate for Toronto-area conditions (based on NRCan residential energy data).
Natural gas heaters are fixed in place, which affects layout flexibility. If the patio area is frequently reconfigured, a fixed heater may not suit the use pattern.
Electric infrared heaters
Electric infrared heaters work differently from convection-based propane units. Rather than heating the air — which wind disperses immediately — they emit radiant heat that warms surfaces and people directly. This makes them more wind-tolerant in exposed conditions.
Output is typically measured in watts rather than BTU. A 2,000 W infrared heater produces roughly 6,800 BTU/h of radiant heat. That's lower than a propane mushroom heater, but the radiant format means the heat is directed rather than dispersed. Ceiling-mounted or wall-mounted infrared units positioned 2–2.5 metres above seating are more efficient per watt than freestanding convection heaters in windy conditions.
Cold-weather considerations for electric units are simpler than for gas: there is no fuel supply variability. The key requirement is a weatherproof outdoor electrical circuit rated appropriately for the load. A licensed electrician should handle installation for any hardwired unit.
Fire tables and fire pits
Propane or natural gas fire tables provide radiant heat from an open flame, typically in the 40,000–60,000 BTU/h range for larger units. The heat is concentrated near the flame and declines sharply with distance. They are better suited as supplemental warmth for smaller, close-gathered seating arrangements than as primary heaters for larger spaces.
Wood-burning fire pits are subject to municipal burn bylaws in most Canadian cities. Toronto, for example, prohibits open burning in most residential zones. Calgary and Vancouver have similar restrictions. Checking the applicable municipal bylaw before purchasing a wood-burning unit is a necessary step.
Combining heat sources
The most effective winter patios in Canada typically layer two sources: a primary heater (natural gas or high-output propane) for the space overall, and a secondary radiant source (infrared panels or fire table) for the seating zone. This allows the primary unit to maintain background temperature while the secondary source addresses personal warmth at close range.
For reference on energy consumption and outdoor heating safety standards applicable to Canadian conditions, the Natural Resources Canada site provides relevant data on appliance ratings and efficiency classifications.