If you’re looking to transform your traditional fireplace into a modern, efficient heating solution, the answer is a resounding yes: you can absolutely put an electric fireplace insert into an existing fireplace. This upgrade is not only easy to accomplish but also offers a safer, cleaner, and more energy-efficient alternative to wood or gas. 

In this guide, we’ll answer your most common questions, share expert tips, and walk you through the installation process—so you can get cozy, fast. 

White living room with brick fireplace and electric fireplace insert with double mantels in white.

Why Add an Electric Insert to an Existing Fireplace? 

The Benefits at a Glance: 

  • Easy installation—no venting or gas lines required. 
  • Safe and clean—no open flames, soot, or emissions. 
  • Instant ambiance—realistic flame effects with or without heat. 
  • Remote-controlled comfort—adjust heat and flame from your couch. 

With options that range from wifi-enabled inserts to plug-in log sets, an electric fireplace insert is an effortless way to breathe new life into your old hearth. 

Side by side images of before and after a fireplace project with a new linear electric fireplace.

How to Install an Electric Fireplace Insert in an Existing Fireplace 

The process is easier than you might think. Most electric fireplace inserts are designed to slide into a standard masonry or prefabricated fireplace opening. 

Here’s how to do it: 

  1. Measure your firebox.
    Height, width, and depth are key to choosing the right insert size. 

  2. Choose your insert
    Options include firebox-style inserts, log sets, and infrared models.
    Pro tip: Our experts recommend choosing a model with adjustable flame effects and thermostat control for the best experience. 
  3. Prepare the space
    Clean out any remaining ash or debris.
    If the existing chimney is still open, seal it off to prevent drafts. 

  4. Plug it in
    Most units plug into a standard 120V outlet.
    No special wiring required. 

  5. Slide it in and enjoy 

Place the insert inside the firebox, adjust the trim if included, and turn it on. 

Need help selecting the right model? Chat with one of our fireplace pros or browse our Best Electric Fireplace Inserts for Existing Fireplaces guide. 

Side by side images of before and after a fireplace project with new linear electric fireplace.

Frequently Asked Questions 

Can I just plug the insert into a wall outlet? 

Yes. Most inserts are plug-and-play. For larger units with higher wattage, a dedicated 15-amp circuit is ideal, but many homeowners use a standard outlet safely. 

Will I lose heat up the chimney? 

Nope. Since electric inserts don’t use combustion, there’s no need for venting. In fact, sealing the chimney improves efficiency. 

Is this a DIY project? 

Absolutely. If you can lift the unit and plug it in, you can do it yourself. That said, we recommend hiring a pro if you’re adding custom trim or hardwiring the unit. 

Shop Electric Fireplace Inserts for Existing Fireplaces 

At Electric Fireplaces Direct, we make it easy to find the perfect insert for your space. Our curated selection includes: 

All backed by our expert support, free shipping, and satisfaction guarantee. 

Ready to make the switch? 

Explore our full collection of electric inserts for existing fireplaces and give your hearth a modern makeover today.