What this covers
A gas insert is a sealed firebox that slides into an existing masonry fireplace, turning an open wood-burning opening into a gas fireplace with a glass front. The company inspects the firebox and chimney first, then measures the opening to choose an insert that fits. Venting usually runs through flexible liners inside the old flue, one for exhaust and one for combustion air. A licensed gas fitter runs or extends the gas line and connects the unit. The surround panel closes the gap to the old opening, and the installation is inspected where required.
When to call
- A wood-burning fireplace that is rarely used because of the work and the draft.
- An opening that loses heat up the chimney when the fireplace is not in use.
- A fireplace being rebuilt after smoke or chimney damage.
What to expect
- InspectThe firebox and chimney are inspected and the opening is measured.
- ChooseAn insert, liner and surround are selected to fit the opening and the room.
- InstallThe liner is run, the insert set, and the gas line connected by a licensed fitter.
- CheckThe unit is tested, the surround fitted, and the installation inspected where required.
Get a certified company
Look up a certified company by ZIP code. Every company's license, insurance and trades are verified before it is listed, and placement is never paid.
Questions people ask
Why does the chimney need a liner?
Most inserts are designed to vent through their own sealed pipes. The liner carries exhaust out and brings combustion air in, separate from the old masonry flue.
Does the chimney have to be in good shape?
It has to be sound enough to hold the liner and its cap. Cracked crowns, loose bricks or a damaged flue are repaired first.
Is a gas line already needed?
Yes. If the house has gas, a licensed fitter extends a line to the fireplace; if not, the company discusses whether another fuel or an electric insert suits better.
Related: Fireplace installation · Chimney repair · Gas line installation · All specialty interiors
This page describes what the service involves. The company you hire sets the scope, the schedule and the price, and your contract is with that company. We verify credentials and collect reviews from real jobs. We do not guarantee any company's workmanship. Safety steps are general guidance. When in doubt, leave the home and call 911.