Mason-Lite 84" Linear Gas Fireplace - 12" B-Vent

Linear Burner

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72 in. Natural Gas Alpine Linear Burner for LMFP84 Fireplace

72 in. Liquid Propane Alpine Linear Burner for LMFP84 Fireplace

84 in. Natural Gas Linear Drop-In Burner With LED Lights For Use With LMFP84

84 in. Liquid Propane Linear Drop-In Burner With LED Lights For Use With LMFP84

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Mason-Lite Fireplaces are designed as factory-built blocks to be assembled on-site. These fireplaces may be installed on either combustible or non-combustible floors. In order to function, the system requires a 12” B-vent chimney.

Looking for a contemporary style for your new fireplace? Look no further than Mason-Lite. Mason-Lite provides safe, yet esthetically beautiful, linear fireplaces for your indoor and outdoor living space.

At Mason-Lite we have been making custom masonry fireplaces for years with great success. Mason-Lite is proud to present our semi-custom linear fireplace line that spans from 4 foot up to 10 foot wide. We have tested 7 new models to the ANSI Z 21.50 standard for Vented Decorative Gas Appliances. This gives you even more peace of mind when using our Custom Linear units. Please see the list below of the units that we tested. All of these units come with a shortened 22.5″ finished opening height that gives you that linear look that is so popular today.

Why Choose Mason-Lite:

Products Features and Benefits:

  • Available in - LMFP 48”, 60”, 72”, 84”, 96”, 108”, 120” wide model
  • Class A chimney accepted
  • ANSI Z21.50 compliant
  • Glassdoor tested & listed
  • Square sides - 90º angle in rear corners
  • Choice of flush hearth or burner trough
  • Units available with & without burner trough
  • BTUs starting at 85,000 to 200,000, depending on model
  • Standard sizes are designed to use single or dual 12” B-vent chimney
  • Available with Golden Blount Alpine Burner & Warming Trends Crossfire Burner
  • Custom widths also available including, but not limited to, corners & see-throughs (meet NFPA211 requirements)
  • Modular Pre-cast fireplaces reduce labor and assembly time
  • Made in the U.S.A


Model LMFP84
Dimension A 97"
Dimension B 87"
Dimension C 84"
Dimension D 81"
Framing Dimension (Non-combustible floor system) 102" (W) x 40.5" (H1) x 64.25" (H2)
Floor Area 98" x 28" (19 ft²)
H-Burner BTU/HR 140,000
Gas Log Burner BTU/HR 125,000
Mortar, Rebar, and Ready Mix Concrete 290 lbs.
Weight 2490 lbs.
Flue 12” Ø
Required Items 12" B-vent Chimney
Style Contemporary
Installation Type Flush Installation / Corner / Internal Wall / Full Projection
Certification ANSI Z21.50 compliant
Warranty Limited lifetime warranty
*NOTE: Firebricks Panel is not included in any custom*



Attention: You may need a residential building permit to install a Mason-Lite Fireplace. Consult local jurisdictions before you get started!