An electric fireplace insert is a self contained unit that fits inside an existing fireplace opening, usually a masonry or wood burning firebox that is no longer in use. It converts that opening into a working electric fireplace without any demolition. The insert slides into the cavity, connects to power, and produces a flame effect with optional supplemental heat.

No demolition is required in most cases. An insert is designed to sit inside the opening you already have, which is the main reason people choose one over a built in firebox. Measure the width, height and depth of your existing opening before ordering, because the insert has to clear the interior dimensions on all three sides.

An insert goes into a fireplace opening that already exists. A firebox creates a fireplace where there was none, by being framed into a wall or a custom surround. If you have an old wood burning fireplace you want to stop using, you want an insert. If you are building a fireplace from scratch, you want a firebox.

Electric fireplaces produce no combustion, no smoke and no fumes, so no venting, chimney or gas line is required. If your existing chimney is no longer in use, it is usually capped or blocked off during installation to stop drafts. Check with a qualified contractor before sealing any flue.

It depends on the model. Plug in units connect to a standard 120 volt household outlet and can usually be installed without an electrician, provided the circuit can carry the load. Hardwired models that run at 208 or 240 volts must be connected by a licensed electrician and typically require a dedicated circuit.