How do I measure my fireplace opening for glass doors?
Measure the finished face of the opening — width at the top, middle, and bottom, and height on the left, center, and right — because masonry openings are rarely perfectly square. Use the largest width and height so the door frame fully covers the opening, and note whether the surround is flat brick or raised, uneven stone.
Measure the face, not the firebox
Glass doors mount to the outside face of the opening, so you're sizing the visible opening, not the interior box. Take three widths — top, middle, and bottom — and three heights — left, center, and right. Older masonry settles and bows, so these rarely match, and the door frame has to cover the biggest of each. Note the surround material too: flat brick seats and seals differently than rough stacked stone.
Standard door versus custom
Many openings take a stock-size door with an adjustable frame that spans a range of dimensions. An opening that's badly out of square, oversized, or bordered by protruding stone may need a custom door or a spacer to mount against a flat surface. Measuring all six points upfront tells us which way it goes — and keeps you from ending up with a door that leaves gaps at the corners where the opening drifts out of true.
One note where doors meet gas
If your fireplace runs gas logs, how the doors are operated depends on the set — vented logs are burned with the doors open, and ventless has its own operating rules — so the door choice and the log set have to agree. We factor that in rather than treating the door as a standalone part. Bring your measurements to the showroom or have us come confirm the opening is square. Call (828) 545-0525 or visit our Asheville showroom.
Related questions
- How do I measure my fireplace for a gas insert?
- How do I measure my firebox for gas logs?
- How do I measure a fireplace with an arched opening?
- Do I measure firebox height to the damper or to the top of the opening?
- What measurements does a fireplace dealer need before quoting an insert or log set?
- How many BTUs per square foot do I need to heat a room with a fireplace?
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