Gas Fireplace Inserts and Wood-to-Gas Conversions

Wood is almost never the main heat in Chicago homes; the Census puts it at about 0.02 percent in the city. The fireplace is for evenings, and many owners find hauling wood and cleaning ash isn't worth it for a few fires a winter. Meanwhile the open firebox loses heated air up the chimney all season.

A gas insert solves both. It is a steel firebox that slides into the masonry opening, closed with glass, and vents through a liner run up the existing chimney. You get a real flame on a switch or remote, and the old opening no longer pulls warm air out of the room.

Signs you need this

• A wood fireplace you rarely use because of the work
• Cold drafts from the fireplace all winter
• A gas line already near the fireplace or basement ceiling below
• A sound masonry chimney that could carry a liner
• Wanting heat in one room without turning up the furnace

How we do it

1. Measure and quote, freeWe measure the firebox, check the chimney and liner path, and look at where gas can reach the fireplace.
2. Choose the unitWe go over sizes and styles that fit your opening, and the written quote lists the insert, liner and gas line.
3. Prepare the chimneyThe flue is inspected and swept if needed, and any repair to the firebox or chimney top is done first.
4. Install and testThe insert goes in, its liner runs to the top with a cap, the gas is connected and the unit is fired and leak-checked.

What goes into a gas insert install

There are three parts to the job: the insert itself, a liner that runs from the insert to the top of the chimney, and gas piping to the fireplace if there isn't any. Inserts installed typically run $2,000 to $5,000 in 2026, and running a gas line to the fireplace typically adds $500 to $1,000+.

Nicor Gas also points out that flexible yellow CSST gas tubing should be properly grounded to the home's electrical system, because a nearby lightning strike can damage it. When we run or connect CSST, we check that it is grounded.

Is my chimney ready?

Most older Chicago masonry chimneys can take an insert once the firebox and flue are checked. A cracked crown, a loose top or failed flashing should be fixed before a new appliance goes in. If your house is in a Chicago Landmark district, interior inserts usually don't change the outside, but any cap or chimney-top work goes to the Historic Preservation Division with the permit. We check what your city requires.

Carbon monoxide alarms

Chicago requires a CO alarm inside any bedroom that has a fireplace or fuel-burning appliance, on top of the state rule of an alarm within 15 feet of every sleeping room. If the insert goes into a bedroom fireplace, the alarm goes in that room.