How do I measure my firebox for gas logs?
For gas logs, measure your firebox front width, rear width, and depth, plus the height from the floor to the top of the opening. Log sets are sized off those numbers with clearances already built in — you don't fill the box wall-to-wall. Give us all four measurements and we'll match a set that leaves the flame room to breathe.
The four numbers a set is chosen from
Front width is the widest span, measured across the front of the opening. Rear width is across the back wall, which in a masonry box is narrower. Depth runs from the front edge of the firebox floor to the back wall. Height is from the floor up to the top of the opening — and note the damper height too, since it is usually lower. A gas log set is sold by a size that already accounts for the burner pan and the air gap the logs need around them.
Logs don't fill the firebox — and shouldn't
The most common mistake is choosing the biggest set the front width allows. Both vented and ventless sets need clearance from the side and rear walls so flames don't impinge on brick and soot everything black. In practice the rear width and the depth govern the size more than the front width does. Vented sets also need enough depth and an open damper to vent properly; ventless sets carry tighter clearances and a room-size BTU limit. We steer you to the set that fits with margin, not the one that barely crams in.
Fuel and the connection are our part
One detail people miss: a natural-gas set and a propane set use different orifices, and the wrong fuel setup burns sooty and yellow. That matters here, where it's natural gas along the Asheville and Hendersonville mains but propane out in Fairview, Candler, Brevard, and the cabins. Connecting the set to a licensed, pressure-tested gas line is our work — NC law requires a licensed gas contractor, and that's us. Send your four numbers or have us measure it. Call (828) 545-0525.
Related questions
- What size gas logs do I need for a 36-inch fireplace?
- My firebox is narrower at the back than the front — which width do I use?
- How do I measure firebox depth correctly?
- What do front width and rear width mean on a gas log sizing chart?
- When a gas log set is called 24 inches, what does that measurement actually refer to?
- How many BTUs per square foot do I need to heat a room with a fireplace?
Still deciding? Talk to a real installer.
Free assessments across Western North Carolina — no pressure, straight answers.