How much does it cost to run a natural gas line to my detached garage for heating in Ottawa?

Running a natural gas line to a detached garage in Ottawa typically costs $1,500 to $4,500 for the gas line work alone, depending on the distance from your home's gas meter to the garage and whether the line runs underground or overhead. Add another $1,500 to $3,500 for the unit heater itself, installed and connected — so your all-in budget for a complete heated garage system should realistically be $3,000 to $8,000 depending on complexity.

The distance is the biggest cost driver. If your detached garage sits 10 metres from the house, you're in a very different situation than a garage 30 metres away at the back of a large lot. Underground runs require trenching — and in Ottawa, that trench needs to be deep enough to protect the pipe from frost and mechanical damage, typically 600 millimetres or more. Trenching through an established driveway, interlock, or landscaping adds significant cost because those surfaces need to be properly restored afterward. If you're running a line across a finished driveway, budget for that disruption.

Ottawa's climate makes this investment genuinely worthwhile. Heating a garage in a city that regularly hits -25°C or colder transforms the space from a frozen storage box into a usable workshop, a comfortable place to work on vehicles, or simply a garage that keeps your car warm enough to start reliably on brutal January mornings. A properly sized natural gas unit heater — typically 30,000 to 75,000 BTU for a standard two-car garage — will heat the space quickly and operate at a fraction of the cost of electric resistance heating.

There are two permits involved here, and both are non-negotiable. The gas line work requires a Enbridge Gas permit and must be performed by a licensed gas fitter (a Red Seal gasfitter or a licensed plumber with gas fitting credentials). The unit heater installation also requires a permit and inspection. Any electrical connections to the heater require a separate ESA permit and a licensed electrician. Skipping these permits is not worth the risk — unpermitted gas work voids your home insurance and creates genuine safety hazards.

One thing worth planning ahead for: if you're trenching for a gas line, seriously consider running a conduit for electrical at the same time. Trenching is the expensive, disruptive part — adding a 60-amp electrical conduit to the same trench while it's open costs relatively little in incremental labour and gives you the infrastructure for better lighting, power tools, or an EV charger down the road without ever having to dig again.

Get at least three quotes that clearly specify the linear footage of pipe, the trench depth and restoration plan, the BTU rating and model of the heater, and which party is responsible for pulling permits. If you're ready to find qualified gas fitters and garage heating contractors in the Ottawa area, you can browse through the Ottawa Construction Network directory at justynrookcontracting.com/directory to compare local professionals who do this kind of work regularly.