TimberFire Large Looks for Large Fireplaces Shown: 36" TimberFire Logs on LD36 Hearth Kit for Natural Gas. Minimum Depth Required = 24" Logs stack about 26" - 30" in height Flame shown here shoots to 48" in height, consuming approximately 200,000 BTU/hour. Actual flame height may vary based on gas supply (pressure and volume). Available in 30", 36", 42" 48", 54", 60", 66", 72", 84" and 96" log set widths.