How Much Does It Cost to Install a Gas Fireplace Insert?
Our listed chimney sweep and cleaning prices start at $59, and chimney repair starts at $49; HomeGuide’s 2026 typical U.S. gas fireplace insert installation range is $2,000–$5,000 installed. We don’t list an insert-installation starting price, so assess the fireplace and venting before setting a budget.
Our Starting Prices in Denver
| Service | Price |
|---|---|
| Chimney Sweep | from $59 |
| Chimney Repair | from $49 |
| Chimney Inspection | free in-home inspection |
| Chimney Cleaning | from $59 |
Need help now? (720) 780-8924
What Shapes the Gas Fireplace Insert Installation Cost?
HomeGuide’s 2026 estimate for a gas fireplace insert is $2,000–$5,000 installed across the United States. That is a typical market range, not a Denver Chimney Sweep Pros quote. Our published prices cover chimney sweep and cleaning from $59, chimney repair from $49, and a free in-home chimney inspection; they do not give a starting price for insert installation.
The estimate for your home depends on the work the installation actually calls for. Ask the installer to identify the insert, the condition and measurements of the existing fireplace, what venting or liner work is included, whether the gas connection needs attention, and what finishing work is part of the scope. Get those details in writing so you can compare estimates on the same basis.
HomeGuide says a gas insert installation usually takes about one day. That estimate is for the installation, not necessarily any separate work needed to repair the fireplace or prepare its venting.
Which Fireplace Insert Option Fits Your Existing Fireplace?
Choose an option based on how you plan to use the fireplace and what the existing opening and venting can accommodate. An in-person assessment helps establish whether the installation scope needs to include related chimney work.
Gas insert in an existing fireplace
Consider this when you want to convert an existing fireplace to gas. Have the installer check the opening, the proposed insert’s fit, venting, and the gas connection before you select a unit.
Electric insert
Compare this option if you want an electric appliance rather than a gas or solid-fuel insert. CDPHE says a masonry fireplace may be used on an Action Day with an electric device if local rules allow it.
Wood or pellet insert
These burn solid fuel, so Denver-area emission standards and Action Day restrictions matter. CDPHE notes that installation standards apply separately from certain use exemptions, including the exemption for some devices above 7,000 feet.
What to Gather Before You Request a Gas Insert Estimate
A few observations can help an installer understand the project before choosing equipment. Do not remove fireplace parts or disconnect gas fittings to collect this information.
- The fireplace opening — Measure the opening’s width, height, and depth if you can do so safely. Share the measurements as a starting point; the installer still needs to verify fit at the home.
- Photos of the fireplace — Take clear photos of the opening and visible surrounding masonry. Include any cracks, damaged surfaces, or missing parts so the installer knows what to inspect.
- Existing appliance and vent details — Note whether the fireplace is currently wood-burning, gas, or unused, and provide any paperwork or model information you already have. Don’t guess at the flue or liner type.
- Your intended use — Tell the installer whether you want regular heat, occasional use, or a change from solid fuel to gas. That context helps focus the assessment on the appliance and venting needed for the plan.
Need help now? (720) 780-8924
How to Check the Installation Scope Before You Book
Use these steps to turn a broad cost range into a clear project scope. Leave gas connections and changes to fireplace venting to the installer.
- Decide what you want the insert to do — Write down whether your priority is supplemental heat, replacing an existing appliance, or changing from wood to gas. Check that the estimate addresses that specific use.
- Record the opening dimensions — Use a tape measure to note the fireplace opening’s width, height, and depth, plus the hearth dimensions. Check that the installer will verify those measurements before confirming the insert.
- Photograph visible conditions — Take photos of the firebox, hearth, and visible areas around the fireplace. Point out stains, loose masonry, or cracks, and ask whether the estimate includes inspection of those areas.
- Ask how venting will be assessed — Ask what existing flue or liner information the installer needs and what the estimate includes if the venting needs work. Check that the scope names the venting parts rather than leaving them unclear.
- Confirm the gas connection scope — Tell the installer whether a gas appliance is already present, but do not disconnect or alter any fittings yourself. Check that the estimate states whether gas-connection work is included or separate.
- Verify the selected insert fits — Give the installer the model information you are considering. Ask them to confirm that its dimensions and installation requirements fit the fireplace and planned venting.
- Ask about local requirements — For an installation in the Denver metro area, ask how the selected device meets current emission standards. Confirm who checks any applicable local requirements before work begins.
- Review the finished scope — Before booking, compare the listed appliance, venting, gas work, repairs, and finishing details against your expectations. Check that the estimate separates included work from anything it excludes.
What Denver-Area Rules Mean for a New Fireplace Insert
CDPHE says indoor burning devices installed in the seven-county Denver metro area must meet current emission standards. Ask the installer to identify how the proposed insert meets the applicable standard before you buy it; the use exemption for some devices above 7,000 feet does not exempt installation from that requirement.
From November through March, CDPHE restricts indoor burning on Action Days in Denver and several surrounding counties. The state posts the Denver-area air forecast daily at 4 p.m.; check the CDPHE indoor burning information for current restrictions and device details.
A gas insert may also involve an existing chimney or vent that needs attention. CSIA recommends annual inspection of gas-heated chimneys because nests, debris, or corrosion can block or damage a flue. Read its homeowner guidance on chimney inspections and have a chimney sweep assess concerns before the appliance is installed.
When a Gas Insert Estimate Should Include Chimney Work
An insert installation and chimney repair are different scopes. These situations can help you identify which work to ask about without assuming that every fireplace needs repairs.
- The fireplace is sound, but you want to change appliances — Ask for an insert installation assessment that checks the opening and venting. Our published chimney prices do not set an insert-installation price, so request a separate estimate for that work.
- You see damaged masonry or loose material — Have the condition inspected before the insert scope is finalized. Our chimney repair price starts at $49, but that is a chimney repair starting price, not an insert-installation price.
- You want the chimney checked before choosing an insert — Our free in-home inspection can assess the chimney before you commit to an appliance. If the concern is routine sweeping or cleaning, those services start at $59; they are separate from insert installation.
Need help now? (720) 780-8924
What to Do Before You Choose a Gas Fireplace Insert
Gather the opening measurements, photos, and any existing appliance information, then ask for an assessment of the fireplace, venting, and gas connection. If you have a chimney concern that needs attention first, see our chimney sweep service in Denver or request a fireplace insert installation service assessment.
A gas insert changes how the fireplace operates, so don’t treat a visible fit as proof that the venting is ready. For questions about doing the work yourself, read whether you can install a fireplace insert yourself before starting.
Frequently asked questions
Does the $2,000–$5,000 range include every gas insert installation?
No. HomeGuide gives that as a typical U.S. installed range for 2026, not a price for every home or a Denver Chimney Sweep Pros quote. Ask for an estimate that lists the insert, venting, gas-connection work, and any separate repairs.
How long does a gas fireplace insert installation take?
HomeGuide says installation usually takes about one day. The actual schedule can also involve separate work identified during the assessment, such as needed chimney repairs or venting preparation.
Should the chimney be inspected before installing a gas insert?
Yes, have the existing chimney and venting assessed before installation. CSIA recommends annual inspections for gas-heated chimneys because nests, debris, and corrosion can block or damage the flue.
Do Denver-area emission rules apply when I install a gas insert?
CDPHE says indoor burning devices installed in the seven-county Denver metro area must meet current emission standards. Ask the installer to verify the proposed device against the current requirements before you buy it.
Plan Your Fireplace Insert Installation
We offer free in-home inspections. Contact Denver Chimney Sweep Pros or call (720) 780-8924 to request an assessment.