What is the cost to add a second fireplace to an existing gas line in a Calgary home?

Adding a second gas fireplace to an existing gas line in a Calgary home typically costs $4,000–$9,000 complete, depending on the fireplace type, how far the new unit is from the existing gas line, and the complexity of the venting.

Here's how the costs break down across the main components.

The fireplace unit itself is usually the largest single cost. A quality direct-vent gas fireplace from a reputable brand like Napoleon, Regency, or Valor runs $1,500–$4,500 for the unit alone. Linear models and larger BTU units sit at the higher end. Don't be tempted by bargain units — Calgary's heating season runs roughly October through April, meaning your fireplace accumulates serious operating hours every year. A quality unit with a solid warranty is worth the investment.

Gas line extension is the second major cost. A licensed gas fitter will assess your existing gas line capacity, run a new branch line to the fireplace location, and install the shut-off valve and connection. Depending on distance and whether the line needs to run through walls, floors, or a crawlspace, this typically costs $500–$1,500. This work must be done by a licensed gas fitter — no exceptions. In Alberta, DIY gas line work is illegal and genuinely dangerous.

Venting is often where costs vary most. A direct-vent gas fireplace (the right choice for most Calgary homes) requires a coaxial vent pipe that exhausts combustion gases outside while drawing fresh combustion air in through the same pipe assembly. Horizontal termination through an exterior wall is the most affordable option at $300–$800. Vertical termination through the roof costs more — $600–$1,500 — and requires a building permit for the roof penetration.

Finishing — the mantel and surround — can range from a simple painted drywall surround at $500–$1,000 to a custom natural stone surround at $3,000–$6,000. This is where homeowners have the most flexibility to control costs or splurge on something stunning.

Alberta Permits and Inspections

Every gas fireplace installation in Calgary requires a gas permit from the City of Calgary (or your municipality if you're in Airdrie, Cochrane, Okotoks, or Chestermere). Permit fees run $100–$200. A Safety Codes Officer will inspect the completed installation — the gas connections, venting termination, clearances, and overall code compliance — before you operate the unit. This step is non-negotiable and protects you from insurance liability and safety risk. Unpermitted gas work will be flagged on any future home inspection.

Before the gas fitter extends your line, they'll verify that your existing gas meter and supply line have sufficient capacity to handle the added load. Most Calgary homes have adequate capacity, but if you're also running a high-BTU furnace, hot water heater, and gas range simultaneously, your gas fitter may need to upsize a section of the line — add $300–$700 if that's required.

A Note on Chinooks

If the second fireplace is wood-burning rather than gas, chinook events create a real backdrafting risk as rapid pressure changes can reverse chimney draft. For a second fireplace in Calgary, a direct-vent gas unit is strongly recommended — the sealed combustion system is completely unaffected by chinook pressure swings, outdoor temperature, or wind direction, making it the most reliable choice for supplemental heating during Calgary's unpredictable winters.

Annual maintenance on the new unit should be budgeted at $150–$250 per year — a gas fireplace technician will clean the burner, inspect the ignition system, check the venting, and verify safe operation after each heavy heating season.

Need help finding a licensed fireplace installer for your project? Calgary Fireplaces can match you with local contractors for free — browse fireplace professionals through the Calgary Construction Network directory at calgaryconstructionnetwork.com/directory?trade=fireplaces.