How to Install an Electric Fireplace Insert in an Existing Fireplace: Step-by-Step Guide
How to Install an Electric Fireplace Insert in an Existing Fireplace
Learn how to evaluate fit, electrical requirements, clearances, airflow, fireplace condition, positioning, trim, and installation requirements before adding an electric fireplace insert to an existing opening.
Quick Answer
Installing an electric fireplace insert in an existing fireplace typically involves confirming that the insert fits the opening, verifying electrical and clearance requirements, preparing the existing firebox, testing and positioning the unit, and installing the appropriate trim or surround.
Installation requirements are model-specific. Always use the installation manual for your exact electric fireplace insert as the controlling source for dimensions, electrical requirements, clearances, airflow, mounting, and finishing requirements.
Installing an electric fireplace insert in an existing fireplace can be a practical way to add electric flame effects and supplemental heat without relying on a traditional wood- or gas-burning fire.
Dimensions, electrical requirements, clearances, airflow, mounting methods, and finishing requirements vary by model. The installation manual for the exact insert should control whenever product-specific instructions differ from general guidance.
Can You Install an Electric Fireplace Insert in an Existing Fireplace?
Yes, an electric fireplace insert can be installed in many existing fireplace openings when the opening is compatible with the unit and the required electrical supply is available.
The existing fireplace should also be clean, dry, structurally suitable, and able to accommodate the insert without blocking required airflow.
Potentially DIY-Friendly
- The existing opening already fits the insert.
- The correct electrical supply already exists.
- No structural modification is required.
- No household wiring modification is required.
- The manufacturer permits the proposed installation.
Professional Help May Be Needed
- A new receptacle is required.
- A dedicated circuit is required.
- The unit requires hardwiring.
- The fireplace opening requires significant modification.
- The proposed installation cannot satisfy manufacturer requirements.
Electric Fireplace Insert vs. Electric Log Set
Before beginning the installation, identify what type of electric fireplace product you are installing. The terms are sometimes used interchangeably, but the installation process can differ.
| Type | How It Is Used | Key Installation Considerations |
|---|---|---|
| Electric Log Set | Placed inside an existing fireplace to create the appearance of burning logs and flames. | Fireplace dimensions, electrical access, placement, airflow, and manufacturer instructions. |
| Electric Fireplace Insert / Firebox | Fits into the existing fireplace opening and can provide a more finished, built-in appearance. | Opening width, height and depth; electrical requirements; clearances; airflow; securing method; and trim or surround compatibility. |
Installation Rule
The instructions supplied with the exact product should determine how the unit is positioned, secured, connected, and finished.
What Should You Check Before Installing an Electric Fireplace Insert?
Before moving the insert into the fireplace, confirm that the existing opening, electrical supply, and surrounding installation conditions meet the requirements for your particular model.
| Pre-Installation Check | What to Verify | Why It Matters |
|---|---|---|
| Fireplace Opening | Measure the available width, height, and depth. | The insert must physically fit the opening while maintaining its required installation conditions. |
| Electrical Requirements | Check the model's voltage, amperage, circuit, receptacle, plug, or hardwiring requirements. | An existing outlet should not automatically be assumed to be suitable for every insert. |
| Clearances | Check the model-specific side, rear, top, mantel, floor, and finishing requirements. | Clearance requirements can differ between models and installations. |
| Airflow | Locate the unit's required air intake and discharge areas. | Required airflow should not be blocked by the fireplace opening, flooring, trim, or surrounding materials. |
| Fireplace Condition | Check for debris, moisture, water intrusion, damage, or other conditions that could interfere with installation. | The existing fireplace should provide a clean, dry, suitable location for the electric unit. |
| Installation Manual | Review the instructions for the exact model before making modifications. | The manufacturer determines the product-specific installation, clearance, electrical, and finishing requirements. |
Measure the Existing Fireplace Opening
Measure the usable width, height, and depth of the existing fireplace rather than choosing an insert based only on its advertised size. Compare your measurements with the dimensions and installation requirements for the exact model you plan to install.
Also account for any trim, surround, mounting hardware, power connection, and airflow space required by the manufacturer.
Verify the Electrical Requirements
Many electric fireplaces require an electrical power source for the flame display, controls, and heating functions.
Do not assume that every electric fireplace insert can use the same household outlet or electrical configuration. If installation requires a new receptacle, dedicated circuit, hardwired connection, or another modification to household wiring, use a qualified electrician where required.
Inspect the Existing Fireplace
Remove loose debris and inspect the existing fireplace for moisture, water intrusion, deterioration, or anything else that could interfere with installation.
Moisture Warning
An electric insert does not require the chimney to exhaust combustion gases, but the existing fireplace and chimney area should still remain protected from moisture and other conditions that could affect the electric appliance.
How Do Electric Fireplace Inserts Work?
Unlike wood- or gas-burning fireplaces, electric fireplace inserts do not create a combustion fire. They use electricity to produce the visual flame effect, and models equipped for heating use an electric heating system to provide supplemental warmth.
Depending on the product, controls may allow the flame display, heat output, and other functions to be adjusted independently.
Because there is no fuel combustion inside the electric insert, it does not produce combustion exhaust that needs to be vented through the existing chimney.
Do Electric Fireplace Inserts Need to Be Vented?
No. Electric fireplace inserts do not require a chimney, flue, or vent for combustion exhaust because they do not burn wood or gas.
The existing fireplace must still provide an installation environment that meets the insert manufacturer's requirements for fit, electrical connection, clearance, airflow, and surrounding materials.
What Are the Clearance Requirements for an Electric Fireplace Insert?
Electric fireplace insert clearances are model-specific. Do not assume that clearance measurements published for one fireplace insert apply to another brand, model, or installation.
Check the installation manual for your exact insert for required distances from the sides, rear, top, mantel, floor, trim, and other surrounding materials.
The manual should also be used to determine which materials are permitted around the unit and where required airflow must remain unobstructed.
Do Not Copy Generic Clearance Measurements
The image below illustrates the types of dimensions that may need to be considered when evaluating a fireplace opening, but it should not replace the requirements for your specific insert.
Can You Install an Electric Fireplace Insert Yourself?
A basic electric fireplace insert installation may be suitable for DIY installation when the existing fireplace already accommodates the unit, the required electrical supply is available, and the installation does not require structural or electrical modifications.
| Installation Situation | Recommended Approach |
|---|---|
| Existing opening fits the insert and no modifications are required | Potentially suitable for an experienced DIY homeowner when permitted by the manufacturer instructions. |
| Suitable electrical supply already exists | Verify that it meets the exact model's electrical requirements before use. |
| A new receptacle, circuit, or wiring is required | Use a qualified electrician where required. |
| Existing fireplace requires significant modification | Professional installation assistance may be appropriate. |
| Manufacturer requirements cannot be satisfied | Do not proceed with that installation configuration. |
How to Install an Electric Fireplace Insert in an Existing Fireplace
The exact installation procedure varies by manufacturer and model. Read the installation manual supplied with your insert before beginning, and follow its instructions whenever they differ from general guidance.
1Read the Installation Manual and Test the Insert
Before permanently positioning the insert, review its installation requirements and test the unit according to the manufacturer's instructions.
Confirm that the flame display, heating function, controls, remote control, and other applicable features operate correctly.
2Measure and Prepare the Existing Fireplace
Confirm the fireplace opening measurements one final time and compare them with the insert's dimensional requirements.
Clean loose debris from the firebox and make sure the installation area is dry and suitable for an electrical appliance.
Fit Warning
Do not force an insert into an opening that does not provide the fit, clearance, or airflow required by the manufacturer.
3Address the Existing Chimney and Damper as Required
An electric fireplace insert does not use the existing chimney to exhaust combustion gases. However, the chimney and fireplace should remain protected against water intrusion and other conditions that could expose the electric unit to moisture.
Whether the damper should be closed, sealed, or otherwise addressed depends on the existing fireplace, the insert installation instructions, and how the fireplace may be used in the future.
Do not make permanent chimney or damper modifications based solely on generic installation guidance.
4Verify and Prepare the Electrical Supply
Confirm that the available electrical connection matches the requirements listed for the exact insert.
The power connection should be accessible or positioned as required by the manufacturer without interfering with installation or airflow.
If a new electrical receptacle, circuit, hardwired connection, or wiring modification is required, have the work completed by a qualified electrician where required.
5Position and Level the Electric Fireplace Insert
Carefully move the insert or electric log set into the existing fireplace opening. Center and level the unit according to the manufacturer's installation procedure.
If the model includes leveling feet, brackets, anchors, or other positioning hardware, use those components as directed rather than improvising a mounting method.
6Secure the Insert as Required
Some inserts are designed to be secured using manufacturer-provided brackets or other hardware, while others may use a different installation method.
Follow the instructions for the exact unit and do not drill into or modify the fireplace insert unless the manufacturer specifically directs you to do so.
7Install the Trim or Surround and Perform a Final Test
Install the manufacturer-approved trim, frame, or surround where applicable. Any finishing material used around the insert must comply with the model's clearance, airflow, and material requirements.
Custom Trim Warning
Do not assume that plywood, sheet metal, or another custom finishing material is suitable simply because it covers the gap around the fireplace. Confirm permitted materials and required clearances first.
Once installation is complete, operate the flame display, heating function, controls, and remote where applicable. Confirm that required air intake and discharge areas remain unobstructed.
Common Electric Fireplace Insert Installation Mistakes to Avoid
Fit & Clearance Mistakes
- Do not assume generic clearances apply. Use the requirements for the exact model.
- Do not choose an insert based only on nominal size. Compare actual dimensions and installation requirements.
- Do not block required airflow. Keep air intake and discharge areas unobstructed.
- Do not assume custom trim material is acceptable. Verify material and clearance requirements.
Electrical & Installation Mistakes
- Do not assume every outlet is suitable. Verify the model's electrical requirements.
- Do not permanently position the insert before testing it.
- Do not improvise mounting methods. Use the specified installation method.
- Do not proceed when manufacturer requirements cannot be satisfied.
When Should You Hire an Electrician or Professional Installer?
Consider professional assistance whenever the installation extends beyond positioning a compatible insert in a suitable existing opening.
Use Professional Help When the Project Requires
- A new electrical receptacle
- A dedicated circuit
- A hardwired electrical connection
- Household wiring changes
- Substantial modification of the fireplace opening
- Installation work you cannot complete in accordance with the manufacturer's instructions
If the required installation conditions cannot be met, choose a different insert or installation approach rather than modifying the product or ignoring its requirements.
Choosing an Electric Fireplace Insert for an Existing Fireplace
The right electric fireplace insert is not determined by appearance alone.
Check the Existing Fireplace
- Usable width
- Usable height
- Usable depth
- Fireplace condition
- Electrical access
Check the Insert
- Actual dimensions
- Electrical requirements
- Installation method
- Heating capability
- Clearances and airflow
- Trim or surround requirements
You can explore electric fireplaces and compare available options based on the requirements of your existing fireplace.
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SimpliFire
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Before You Buy
Every product comes with installation information specific to that unit. Review the product documentation before selecting an insert for an existing fireplace.
Frequently Asked Questions About Electric Fireplace Insert Installation
Can you put an electric fireplace insert in an existing fireplace?
Yes, an electric fireplace insert can be installed in many existing fireplaces when the opening fits the unit and its electrical, clearance, airflow, and installation requirements can be satisfied. Do not install a model when the existing fireplace cannot meet its manufacturer-specified requirements.
Do electric fireplace inserts need a chimney or flue?
No. Electric fireplace inserts do not burn fuel and therefore do not require a chimney or flue for combustion exhaust; the existing fireplace should still be dry and suitable for the electric appliance.
Do I need an electrician to install an electric fireplace insert?
Use a qualified electrician where a new receptacle, circuit, hardwired connection, or household wiring modification is required. A straightforward installation may not require new electrical work when a suitable power supply already exists and meets the exact model's requirements.
Can I plug an electric fireplace insert into an existing outlet?
Only use an existing electrical connection when it satisfies the voltage, amperage, circuit, grounding, location, and connection requirements specified for your insert. Do not assume an existing fireplace-area outlet is suitable for every model.
How do I know what size electric fireplace insert will fit my fireplace?
Measure the usable width, height, and depth of the existing fireplace and compare those dimensions with the insert's actual dimensions and installation requirements. Account for required clearance, airflow, electrical access, mounting hardware, and trim rather than relying only on the advertised fireplace size.
Are clearance requirements the same for every electric fireplace insert?
No. Side, rear, top, mantel, floor, trim, and other clearance requirements can vary by model, so use the installation manual for the exact insert rather than applying measurements from another fireplace.
Should you close or seal the fireplace damper when installing an electric insert?
Follow the insert manufacturer's instructions and consider the condition and future use of the existing fireplace before altering the damper. Do not permanently modify or seal a chimney or damper based solely on generic installation guidance.
Can an electric fireplace insert be installed directly on carpet?
Only install an electric fireplace insert on flooring or surfaces permitted by the manufacturer. Do not use a surface that blocks required airflow or violates the model's floor and clearance requirements.
Final Thoughts on Installing an Electric Fireplace Insert
Installing an electric fireplace insert in an existing fireplace starts with compatibility, not the installation itself.
Confirm the fireplace opening dimensions, electrical requirements, clearances, airflow, existing fireplace condition, and installation method before positioning the unit.
Bottom Line
For a compatible installation, follow the instructions supplied with the exact insert when preparing the fireplace, connecting power, positioning and securing the unit, installing the trim or surround, and completing the final operational check.
When new electrical work or significant fireplace modifications are required, use the appropriate qualified professional rather than adapting the installation beyond the product requirements.
Need Help Choosing an Electric Fireplace Insert?
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If you have questions about choosing an electric fireplace insert for your existing fireplace, contact us.
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