Vent route, gas line and finish, where your budget goes

What affects the cost to convert a fireplace to gas?

People say gas fireplace and mean very different things. One is a gas log set placed in a wood-burning fireplace you already have. Another is a sealed gas insert that slides into that fireplace. The third is a brand-new gas fireplace built into a wall where there was nothing before.

Each uses the house differently, so each has a different budget. The log set leans on the existing chimney. The insert needs its own venting run up that chimney. The new unit needs a vent path of its own and a place in the wall to sit.

Knowing which one you're pricing is the first step to comparing quotes fairly.

It also helps to decide early what the fireplace is for. If it's mainly for the look on a cool evening, a log set may be all you need. If you want it to warm the room, an insert or a heater-rated direct-vent unit is the better fit, and that choice changes the budget more than any finish ever will.

Gas log installation cost

Vented gas logs may involve relatively little building work when the existing fireplace, chimney and gas supply are suitable. The selected model determines cleaning, inspection, installation and damper-opening requirements. Any required repairs or supply work belong in the estimate, and a permanent damper stop must remain effective as the manual requires.

Because nothing is built, the gas log installation cost is mostly the log set itself and the gas line to the firebox. The set's size, its log style and its controls, from a manual valve to a remote, move the price from there.

Where the existing fireplace and supply are suitable, vented logs can be a relatively limited conversion. Include necessary repairs, preparation and gas work before comparing that option with an insert or new fireplace.

Gas fireplace insert installation cost

A direct-vent insert fits a suitable existing opening and adds its specified air and exhaust connections. A surround may close the visible gap, while clearances and retained chimney condition still need checking. These details affect both suitability and installation cost.

Your selected insert uses the combustion-air and exhaust arrangement approved for its model. Liner lengths, terminations and connections need to follow those instructions. Do not assume that every kit uses two identical full-height liners or permits the same existing chimney.

A heater-rated insert can provide useful room warmth, with output and controls depending on the model. Compare its specifications and the room heat demand rather than assuming all of its heat remains indoors.

A new built-in gas fireplace

A new built-in gas fireplace can add enclosure, venting, gas supply and finish work where no fireplace existed. The scope depends on the selected model and room. It may be more extensive than fitting logs in a suitable hearth, but not every project follows the same cost order.

Direct-vent units are flexible about where they go, since they can vent through a wall instead of needing a chimney. That flexibility is why they suit rooms built without one. It's also where the vent route, below, starts to matter a great deal.

Plan the surrounding wall early too. The enclosure has to respect the unit's clearances to wood framing, and building it right the first time is far cheaper than opening a finished wall later.

How the vent route affects the quote

A direct-vent model uses its approved air and exhaust components; some use concentric pipe and others use separate paths. Permitted runs, elbows, rises and terminations come from the exact manual. An exterior wall is useful only when the proposed route and clearances are allowed.

A unit on an interior wall, or one under a second floor, needs a longer run up through the house or across to an outside wall, with framing and finish work to hide it. Vertical runs through the roof add roof flashing, a storm collar and a termination cap.

The vent's outside termination also has to sit certain distances from windows, doors and other openings, as the manual and the fuel gas code set out. Sometimes that clearance, more than anything, decides where the fireplace can go.

The gas line

Every gas fireplace needs a gas supply, and running it is a gas contractor's work, which your quote names. The cost depends on the distance from the meter or the manifold to the fireplace, how easy the route is, and whether the existing gas line can carry the extra load.

On propane, it also depends on the tank. The unit is ordered for the gas you have, since the rating plate names natural gas or propane and some units can't be converted in the field. A new gas line or appliance will likely need a permit, which the building official for your address decides.

The finish around the unit

The last part of the budget is what you see. A simple painted surround or trim panel costs the least and goes in quickly. Tile, stone, a raised hearth or built-in shelving around the unit add material and labor quickly, and they're where two quotes for the same fireplace can end up far apart.

Whoever does the finish, the unit's listing sets clearances to combustible materials above and around it, including any mantel. Your quote should spell out the finish and who handles it, so there are no gaps between the trades.

Price your gas fireplace with us

Torn between gas logs, a sealed insert and a brand-new unit? Our family-run pros look at your room and your chimney during a free visit, map the vent route and write out a price for each option. Your first service receives 10% off. Start your gas fireplace installation plan at (352) 675-6366.