Fireplace Inserts for Existing Fireplaces

Upgrade your old fireplace with a modern fireplace insert designed for existing openings. Choose from electric, gas, and ethanol - all engineered to improve efficiency, enhance flame realism, and simplify installation.

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Shopping Guide: Fireplace Inserts for Existing Fireplaces

What Is a Fireplace Insert?

A fireplace insert is a self-contained heating unit designed to fit inside an existing masonry or factory-built fireplace opening. Inserts improve heating efficiency, update the look of outdated fireplaces, and reduce heat loss compared to traditional open fireplaces.

Types of Fireplace Inserts

Electric Fireplace Inserts

No venting required (plug-in installation for many models)
Quick, simple upgrades for existing openings
Realistic flame effects with low maintenance
Best for supplemental heat and everyday ambiance

Gas Fireplace Inserts (Natural Gas or Propane)

Real flame with strong heat output
Ventless and direct vent options (varies by model)
Great for homeowners prioritizing heat performance
Professional installation is typically recommended

Ethanol Fireplace Inserts

Ventless and chimney-free
Real flame without a gas line or hardwiring
Clean-burning bioethanol fuel (varies by product)
Popular for modern, minimalist designs

Water Vapor Fireplace Inserts

Flame illusion created with water mist technology
No real combustion
Safe-to-touch visual effect (great for kids and pets)
Ideal for homes and commercial spaces prioritizing safety

Do Fireplace Inserts Increase Efficiency?

Yes. Traditional open fireplaces can lose a significant amount of heat through the chimney. Inserts are more enclosed and controlled, which can improve heat retention and provide more efficient supplemental heating.

How to Choose the Right Insert

Opening size: measure width, height, and depth of your existing fireplace.
Fuel availability: outlet access, gas line access, and venting requirements.
Heat goals: match BTU rating or coverage area to your room size.
Style preference: traditional logs vs modern flame presentations.

Not sure how to measure or need help deciding? Call or text our experts at 866-713-2399.

Frequently Asked Questions about Fireplace Inserts for Existing Fireplaces

What is the difference between a fireplace insert and a built-in fireplace?

A fireplace insert is designed to fit into an existing fireplace opening. A built-in fireplace is installed into the framing during construction or renovation and does not require an existing fireplace. Some electric fireboxes can be installed as both a built-in fireplace and an insert. Check the product manual to verify.

How much does a fireplace insert cost?

Fireplace inserts typically range from under $1,000 for electric models to several thousand dollars for larger gas or premium electric units. Installation costs vary depending on fuel type and venting requirements.

Do fireplace inserts need a chimney?

Electric, ethanol, water vapor, and ventless gas inserts do not require a chimney, making them ideal for homes without existing venting. Direct vent gas inserts do require outside venting, but the system is much simpler than a traditional chimney and can run horizontally through an exterior wall or vertically through the roof.

Are fireplace inserts more energy efficient?

Yes. Inserts are sealed systems that reduce heat loss and provide more controlled heating compared to open fireplaces.

Can I install a fireplace insert myself?

Some electric inserts are plug-and-play. Gas inserts and certain installations should be handled by licensed professionals to ensure safety and compliance.

How do I measure for a fireplace insert?

Measure the width, height, and depth of your existing fireplace opening. Be sure to measure at the front and toward the back of the opening, as some fireplaces narrow in depth. Compare your dimensions to the insert’s required framing and clearance specifications to ensure proper fit.