Will This Fireplace Insert Fit My Fireplace?
Free Sizing Tool
Pick the inserts you are considering and we will tell you instantly whether they fit your existing fireplace. No callbacks, no guesswork.
- 1Choose Fuel Type
- 2Select Inserts
- 3Enter Dimensions
- 4Get Results
What type of insert are you considering?
We will show you the inserts available in that fuel type.
Select the inserts you are considering
Pick up to 3 models. We will check each against your firebox dimensions in the next step.
Enter your firebox dimensions
All five measurements in inches. Round down to the nearest quarter inch — never round up.
Your Fit Results
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Contact a SpecialistHow to Measure Your Fireplace for an Insert
Accurate measurements are the difference between an insert that drops in and one that gets returned. You will need a tape measure and about ten minutes. Measure in inches and round down to the nearest quarter inch — never round up.
Front Opening Width (A)
Measure across the front of the firebox, from the inside of the left wall to the inside of the right wall. If your fireplace has an arched top, measure at the widest point.
Front Opening Height (B)
Measure from the floor of the firebox straight up to the lowest point of the lintel or arch. If the lintel is uneven, use the shorter side.
Depth (C)
Measure from the front face of the firebox straight back to the rear wall, at the floor. This is the most commonly missed measurement.
Rear Width (D)
Measure across the back wall of the firebox. Most masonry fireboxes taper, so the rear is narrower than the front.
Rear Height (E)
Measure from the floor to the ceiling at the back of the firebox. The rear is usually shorter than the front because of the smoke shelf above.
Frequently Asked Questions
How do I know if a fireplace insert will fit my fireplace?
Measure five dimensions of your existing firebox: front width, front height, depth, rear width, and rear height. Every insert manufacturer publishes minimum opening requirements for each model. If your firebox meets or exceeds every minimum, the insert will fit.
Why does the rear width matter for a fireplace insert?
Most masonry fireboxes taper, so the back wall is narrower than the front. If your rear width is too small, the insert body will not slide all the way in even if the front opening is large enough. This is one of the most common reasons inserts do not fit a fireplace they were ordered for.
Can I install a gas insert in any wood-burning fireplace?
Most gas inserts are designed to retrofit into masonry wood-burning fireplaces with an existing chimney. You will also need a gas line run to the firebox and a co-linear flex liner installed up the chimney.
Do electric inserts have the same sizing requirements as gas or wood?
Electric inserts are generally more flexible because they do not require venting. They still need to fit the firebox dimensionally, but most do not require minimum rear width or depth in the same way a wood insert does.
What if my fireplace is too small for any insert on this list?
If no model fits your dimensions, contact us. We carry compact inserts beyond what is shown here, and a small firebox modification can often open up dozens of options.
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