Johns Manville DB-4X10X1-1/2-800 Duct Board 800 Mf Sheet

Product Description

The JOHNS MANVILLE DB-4X10X1-1/2-800 is a single sheet of Micro-Aire fiber glass duct board rated at 800 MF, designed for fabricating supply and return air duct systems in both residential and commercial HVAC applications. Measuring 1.5 inches thick, 48 inches wide, and 120 inches long, this sheet provides a large working surface for efficient shop or field fabrication. The rigid board construction delivers strong thermal insulation and acoustical attenuation, reducing system noise while limiting heat transfer through duct walls. HVAC contractors and sheet metal fabricators use it as a direct alternative to metal ductwork where weight savings and installation efficiency are priorities.

Micro-Aire duct board is used in new construction and retrofit HVAC projects across light commercial and residential settings. The material is fabricated into supply plenums, trunk lines, branch ducts, and air-handling enclosures using standard duct board tools and scoring techniques. Its inherent flexibility during layout allows contractors to cut and fold complex duct geometries without specialized equipment. Installed assemblies exhibit lower air leakage rates compared to unsealed sheet metal systems, supporting consistent airflow distribution and more stable zone temperatures throughout the conditioned space.

Key Features

• 800 MF fiber glass duct board rated for standard HVAC air distribution systems
• 1.5-inch thickness provides thermal insulation and acoustical performance in a single material
• Large 48-inch x 120-inch sheet format reduces seams and speeds fabrication
• Lighter weight than equivalent sheet metal duct assemblies, reducing installation labor
• Low air leakage characteristics support energy-efficient system performance
• Consistent product density from a dedicated manufacturing process supports repeatable fabrication results

Compatibility

Designed for fabrication of supply and return air duct systems in residential and light commercial HVAC construction where fiber glass duct board meeting 800 MF density ratings is specified.

Installation Notes

Installation should be performed by a qualified HVAC contractor or sheet metal fabricator familiar with fiber glass duct board construction methods. Follow SMACNA Fibrous Glass Duct Construction Standards and local mechanical code requirements for joint sealing, support spacing, and maximum velocity ratings. Use appropriate personal protective equipment, including gloves and eye protection, when cutting or scoring fiber glass board. Seal all joints with approved duct board tape or mastic to maintain system integrity and minimize air leakage.

Technical Specifications

• Product Type: Fiber Glass Duct Board
• Density Rating: 800 MF
• Thickness: 1.5 inches
• Width: 48 inches
• Length: 120 inches
• Weight: 16.92 pounds

Standard Information

• Brand: JOHNS MANVILLE
• Manufacturer Part Number: DB-4X10X1-1/2-800