How far does a fireplace insert stick out onto the hearth?
Most inserts sit partly inside your firebox and extend several inches out onto the hearth — the front hood, where the glass and controls are, projects past the opening, and the flat surround sits against the wall face. How far varies by model, and it matters because your hearth may need to be deep enough to sit under that projection safely.
Inside and out
An insert is designed to seat most of its firebox inside your existing opening, with the front section and controls projecting forward onto the hearth. That forward hood is where the glass and heat come from, so it needs to clear the opening.
Gas inserts generally project less than big wood inserts, which carry a lot more mass. The number that matters isn't just how far it sticks out — it's how much non-combustible hearth sits under and in front of that projection.
Why your hearth depth matters
Codes and manufacturers require a non-combustible hearth extension in front of the glass, protecting against radiant heat and, on wood units, stray embers. If your existing hearth is shallow, a deeper-projecting insert may need the hearth extended before it's safe.
We see this in older Asheville homes with slim brick hearths and in prefab installs where the hearth is minimal. We check the projection against your hearth on the assessment and tell you if it needs building out.
Measure the hearth too
When you're planning an insert, measure your hearth's depth from the opening outward, not just the firebox. Bring that number along with your width, height, and depth.
We'll match a model whose projection your hearth can handle, or plan the hearth extension as part of the job. Call (828) 545-0525 for a free assessment.
Related questions
- How much smaller than my fireplace opening will an insert's viewing window be?
- Do gas fireplaces and inserts require a hearth extension, and what size?
- What size gas insert will fit my existing fireplace?
- Do fireplace inserts come in different depths?
- What is the surround or flashing panel on an insert and how is it sized?
- How many BTUs per square foot do I need to heat a room with a fireplace?
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