How are see-through fireplaces measured?
A see-through (double-sided) fireplace is measured by its viewing width and height like any unit, but you also need the depth through the wall, since it opens into two rooms. The spec sheet lists the firebox opening plus a rough-opening depth — the wall, peninsula, or partition it sits in has to be built deep enough to house the whole box.
Measured like any fireplace, plus one extra dimension
A see-through fireplace — open on two sides, viewable from two rooms — gets measured by its viewing width and height just like a single-sided unit. The difference is the third dimension: depth through the wall. Because it opens into two rooms, the spec sheet lists both a firebox depth and a rough-opening depth, and the wall, peninsula, or partition it sits in has to be built deep enough to house the whole box. Miss that depth number and the unit simply won't fit the wall you planned it for.
The framing controls the fit
With a see-through, the framing is the real constraint. You can't tuck one into a shallow 2x4 partition — these units need a purpose-built opening with enough depth, width, and height, and clearances to combustible framing honored on both faces. In new construction around Fletcher or Arden, we frame the peninsula to the manufacturer's rough-opening spec from the start. In a remodel, we measure the existing wall first and match a unit that fits it, rather than forcing a box the partition was never built to hold.
Venting a two-sided box
Because both faces are glass, a see-through gas fireplace is almost always direct-vent — sealed combustion, coaxial pipe run out a sidewall or up through the roof, no open chimney required. That venting route has to be planned before the wall is ever closed up. We map the vent run, confirm the depth and clearances, pull the county permit with Buncombe, Henderson, Haywood, or Transylvania, and pressure-test the gas line we run to it. Call (828) 545-0525 for a free in-home assessment before you frame.
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Related questions
- How is heat output split between the two rooms on a see-through fireplace?
- What size gas log set fits a see-through fireplace?
- How do you measure a three-sided, bay, or peninsula fireplace?
- What is the rough opening or framing size for a built-in direct vent fireplace?
- How much wall depth does a built-in gas fireplace need — will it fit in a 2x4 wall?
- How many BTUs per square foot do I need to heat a room with a fireplace?
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