Most Toronto homes are heated one of two ways: a furnace that blows warm air through ducts, or a boiler that circulates hot water through radiators or in-floor loops. If you're replacing your heating system — or renovating — it helps to understand the real differences before you decide.
How Each System Heats Your Home
A furnace burns gas to heat air, then a blower pushes that warm air through ductwork to vents in each room. It's the most common system in newer GTA homes. A boiler heats water and circulates it through radiators, baseboards, or in-floor tubing; the room warms from radiant and convective heat rather than blown air. Many older Toronto homes — especially pre-1960s — use boilers and radiators.
Comfort: The Big Difference
This is where they feel different. Boiler (hydronic) heat is even, quiet, and draft-free, with no blowing dust — many people find it the most comfortable heat there is, and in-floor versions give you warm floors. A furnace heats up faster and, crucially, the same ductwork can carry central air conditioning in summer — something a boiler can't do on its own.
| Factor | Furnace (forced air) | Boiler (hydronic) |
|---|---|---|
| Heat feel | Fast, warm air from vents | Even, silent, radiant |
| Air conditioning | Uses same ducts | Needs separate system |
| Air quality | Can blow dust; needs filters | No blown dust or allergens |
| Hot water | Separate water heater | Combi boiler can do both |
| Best for | Homes with ductwork, want central AC | Radiator/in-floor homes, comfort-first |
Efficiency and Running Cost
Both modern systems are high-efficiency: a 96% AFUE furnace and a 95%+ condensing boiler are comparable on paper. Real-world cost depends more on your home, insulation, and how the system is sized and installed than on the furnace-vs-boiler choice itself. A combi boiler has the added efficiency bonus of handling your hot water without a separate tank.
Which Should You Choose?
In practice, the decision is usually made for you by your home:
- You already have ductwork and want central AC: a furnace (plus AC, or a heat pump) is the natural fit.
- You have radiators or in-floor heating: stick with a boiler — ideally a high-efficiency combi that also makes your hot water.
- You're renovating or building: in-floor radiant from a boiler offers premium comfort, while forced air offers easy central cooling. Many homes end up with a mix.
Still Not Sure?
Every home is different, and the right answer depends on your existing setup, comfort priorities, and whether you need cooling. We install and service both furnaces and boilers across Toronto and the GTA — call us and we'll give you a straight recommendation for your home, not a sales pitch.