Mason-Lite MFP75 75" Semi-Custom Pre-Cast Masonry Firebox Kit

MFP75 Overview

The Mason-Lite MFP75 is a 75 inch semi-custom firebox kit positioned between the standard single-flue lineup and Mason-Lite's fully bespoke custom program. Unlike the 33 through 63, the 75 vents through dual 14 inch Class A UL103 chimneys instead of a single flue, which is what enables the larger opening while staying within UL127 listing. Framing dimensions are 83 inches wide by 72-1/2 inches tall by 30 inches deep; total unit height with mortar is 72 inches, and shipping weight is approximately 3,200 pounds before crating.

Because the MFP75 is semi-custom, several accessories sized for the standard line (factory firebrick liner panels, a Mason-Lite metal base kit, the PureBurn burner) are not published for this size and are typically handled with a custom quote. Buyers pursuing the 75 should plan on hand-laid firebrick (ASTM C1261) for the firebox interior, an installer-supplied anchor plate / damper sized for the 16 inch combined flue path, and structural review for the dual-chimney loading. Outside combustion air uses the MFPST-AK-M see-through air kit because of the 75's square-sided geometry.

Key Features

• 75 inch finished opening width, the largest single-flue-style standard kit
• Vents through dual 14 inch Class A UL103 chimneys
• Hand-laid firebrick required (ASTM C1261); factory panels not available for this size
• Lightweight pre-cast modular concrete construction (50% lighter than site-built masonry)
• Approved for indoor and outdoor installation
• Listed to UL127 with UL103 Class A chimney components, ICC-ES Report ESR-2401
• Approved for multi-story and combustible-floor installations
• Field assembly time of 2-3 hours by a trained installer
• Heat resistant up to 1700 degrees Fahrenheit at 28-day compressive strength
• Ships with high-temperature dry mortar, T-bar lintel, and rebar included
• Approved for vented decorative gas logs per ANSI Z21.60
• Limited Lifetime Warranty (Masonry Fireplace Industries)
• 100% USA sourced and manufactured

Specifications

Warranty

Masonry Fireplace Industries (MFI) provides a Limited Lifetime Warranty on Mason-Lite fireplaces. The warranty covers defects in materials of the modular concrete firebox that adversely affect fireplace performance, for the lifetime of the product from the date of purchase. Coverage applies only to fireplaces installed in the continental United States, Alaska, and Canada.

Specific terms include:

• Coverage is limited to the modular concrete firebox manufactured by MFI. Hardware, foundation, venting, ducts, chimney systems, outside air ducts, and accessories are not covered, even when supplied by MFI.
• Drafting, smoking, and sooting are excluded because they are influenced by site conditions outside the manufacturer's control.
• Glass is warranted against thermal breakage only and only on MFI-manufactured glass-front models. Safety glass or safety screen must be in place when the fireplace is in use.
• The warranty is void when the fireplace is not installed per the published installation instructions, or when there is evidence of misuse, abuse, improper installation, accident, or lack of regular maintenance.
• Damage in transit is not covered.
• Labor costs and indirect costs for component replacement are not covered. MFI may, at its option, repair, replace, or refund a defective covered component.
• Claims must be submitted to MFI in writing by registered mail within 30 days of discovering the defect, including the date of purchase, model and serial number, place of purchase, address of installation, homeowner contact information, and a description of the defect.

Downloads

• MFP75 Spec Sheet (PDF)
• MFP75 Instruction Manual (PDF)
• Mason-Lite Product Catalog (32 pages)
• Wood Burning Clearance & Mantel Guide
• CMU Base Layout Instructions
• Hearth Rebar Locations (All Sizes)
• Seismic Zoning Map
• Metal Base Spec Sheet