How to Install a Wood, Gas, or Electric Fireplace Insert for Cozier Nights

Get fired up with this step-by-step guide

Bry'Ana Arvie
Written by Bry'Ana Arvie
Updated May 11, 2022
A cozy living room with a burning fireplace
Photo: svetikd / iStock / Getty Images Plus / Getty Images


Only DIY if you know what you're doing.

Time to complete

8 hours

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What you'll need:


  • Tape measure
  • Safety goggles
  • Fire extinguisher
  • Gloves
  • Pipe wrenches
  • Grinder
  • Ladder
  • Screwdriver
  • Tin snips


  • Fireplace insert
  • Protective covering
  • Gas cap
  • Pipe dope
  • Cut-off wheels
  • Screws
  • High-temperature silicone
  • Top plate
  • Termination fitting cap
  • Screws
  • Weatherproof cap
  • Cover plate
  • Fireplace sealer

If your traditional fireplace isn’t cutting it, it may be time to switch to a fireplace insert. Designed to fit inside an existing fireplace, an insert is basically a metal box that is (you guessed it!) inserted into a fireplace opening. The cherry on top? You can finish the insert with a decorative surround to give your room a style upgrade. Read on to learn how to install different types of fireplace inserts and when to contact the pros.

10 Steps to Install a Wood-Burning Fireplace Insert

A technician installing a wood fireplace
Photo: Sinenkiy / iStock / Getty Images Plus / Getty Images

The steps to installing a fireplace insert are similar regardless of the type of fireplace—but there are some key differences. Here’s what to do if you’re adding an insert to a wood-burning fireplace.

  1. Measure the Space

    Measure the fireplace to ensure your insert will fit. Use a tape measure to measure the opening height, width, and depth of the top and bottom of the fireplace and the rear width and depth of the hearth.

  2. Place a Protective Covering

    Use a protective covering over your hearth and flooring to protect it from getting scratched up during installation.

  3. Contact an Electrician

    You’ll need to install an electrical outlet inside your fireplace for your insert, so call a professional electrician near you to handle this step.

  4. Cap off Gas Line

    If you’re converting your fireplace from gas to wood-burning, you’ll need to cap off the gas line. First, shut off your gas and use pipe wrenches to unscrew the gas line inside the fireplace. Then apply pipe dope on the threads and cap it off with the fitting size cap.

  5. Remove the Damper

    Without removing your damper, you can’t pass your flue liner through your chimney and insert. Use a grinder and cut off the wheels to remove it. Use eye protection, gloves, fire extinguisher, and protective covering in your workspace. Once you’ve finished, discard all the protective covering you used.

  6. Install the Flue Liner

    This part requires that you’re comfortable going up onto your roof. If you’re not OK with doing that, you can simply call a chimney professional to handle the job. Otherwise, using ladder safety precautions, climb your roof and up to your chimney with your flue liner. Move the chimney cap and feed your flue liner into your chimney.

  7. Make Connections

    Slide your inserts into your fireplace opening. Connect your insert to your electrical outlet and the flue line to the adapter on top of the insert. Use screws and a screwdriver to secure it in place.

  8. Cut the Excess Liner

    After making the connections, cut off the excess liner from the top of the chimney with tin snips and discard it.

  9. Apply Sealant to Your Flue Tile

    Use high-temperature silicone on top of the flue tile, then attach the chimney cap, pressing down for a secure seal.

  10. Install Panels

    Now install the panel to the insert and attach them with screws.

16 Steps to Install a Gas Fireplace Insert

Installing a gas fireplace insert is somewhat similar to the steps above. Here’s what to do. 

  1. Measure your fireplace opening’s width, height, and depth with a tape measure to see what insert you can fit into it.

  2. Contact an electrician to install a duplex receptacle for your insert in the rear of your fireplace.

  3. Contact a plumber to install a gas line to your fireplace if you don’t already have one. 

  4. Remove the existing damper to pass the airflow intake and exhaust liners through the chimney flue. 

  5. Use a grinder and cut-off wheels to remove the damper while using protective equipment such as safety goggles, gloves, fire extinguisher, and protective covering. 

  6. Discard all protective covering used. 

  7. Climb onto the roof with the liners using a ladder. 

  8. Remove the chimney cap and feed the liners through to the insert one by one with a weight at the end for extra support. 

  9. Use a high-temperature silicone sealant on a top plate to seal the flue and keep the weather out. 

  10. Use a termination fitting cap to place your intake and exhaust liners inside it. 

  11. Screw the fitting to your liners, then install a weatherproof cap. 

  12. Connect your insert to its electrical outlet and connect your gas line to your insert. 

  13. Test the gas connection to ensure everything’s working as intended. 

  14. Push the insert into the fireplace opening. 

  15. Use high-temperature silicone to connect liners to the insert. 

  16. Install top glass panel to insert. 

9 Steps to Install an Electric Fireplace Insert

No, you don’t have déjà vu. Installing an electric fireplace insert is a lot like installing a wood or gas fireplace insert—but a bit easier. Here’s what to do.

  1. Measure the width, depth, and height of your fireplace opening using a tape measure.

  2. Remove any of your existing fireplace components if you haven’t already. 

  3. Clean your fireplace of stuck-on dirt and debris. 

  4. Use a ladder to climb onto your roof and install a cover plate over your chimney using silicone if it doesn’t have a good rain cap to protect your insert.

  5. Close and seal your damper using a fireplace sealer. 

  6. Decide if you want to run a cord to the nearest outlet or have an electrician install one to the rear of your fireplace. 

  7. Slide your insert into the opening. 

  8. Connect it to the power source and test it. 

  9. Install the trim. 

DIY Installing a Fireplace Insert vs. Hiring a Pro

If you’re not familiar with climbing on roofs and connecting gas and electrical lines, we strongly suggest you contact a fireplace installation pro near you to do this project. They have the equipment, experience, and safety skills to complete this job successfully and safely. Here is the typical cost to install a fireplace insert if you hire a pro:

  • Wood: $1,000–$1,500

  • Gas: $700–$1,000

  • Electric: $500–$2,000

Need professional help with your project?
Get quotes from top-rated pros.