Gray Flex 16-4GF-8_BAG Silver Insulated Flex Duct R8 16 Inches X 25 Foot Bag

Product Description

The Gray Flex 16-4GF-8_BAG is a silver insulated flexible air duct with an R-8 insulation value, sold in a 25-foot bag. It is designed for use as a Class 1 air duct material and is tested and listed under UL 181. HVAC contractors, sheet metal workers, and mechanical installers rely on this type of insulated flex duct for residential and commercial ductwork systems. The 16-inch inside diameter makes it well-suited for larger trunk runs and high-volume air distribution applications.

The inner core uses an exclusive patented reinforced liner that forms an airtight seal to minimize air leakage. This helps maintain system efficiency and supports compliance with energy codes that require low duct leakage. The fiberglass insulation layer is a minimum of 2 and 5/8 inches thick on the 4GF-8 model, delivering the full R-8.0 thermal resistance rating. The outer jacket is a scrim-reinforced metalized polyester vapor barrier with a silver finish. The jacket is printed with a certification label, foot markers, size data, and performance data every 24 inches, with foot markers every 12 inches, making installation measurement fast and accurate on the job site.

This duct meets a wide range of building and fire code requirements including UL 181, NFPA 90A and 90B, SBCC, HUD 515-2.1, BOCA, ACCA, and ADC. The maximum flame spread rating is 25 and the maximum smoke developed rating is 50, meeting standard Class 1 air duct requirements. The duct handles operating temperatures from -20 degrees Fahrenheit to 250 degrees Fahrenheit and supports a maximum air velocity of 5,500 feet per minute. Pressure rating is 10 inches positive and 3/4 inches W.G. negative per UL 181. Manufactured in the USA.

• 16-inch inside diameter insulated flex duct with R-8.0 thermal resistance, ideal for larger HVAC duct runs
• UL Listed and compliant with UL 181, NFPA 90A and 90B, SBCC, BOCA, ACCA, ADC, and HUD 515-2.1
• Scrim-reinforced metalized polyester vapor barrier jacket with printed foot markers every 12 inches for fast field measurement

Product Highlights

The Gray Flex 16-4GF-8_BAG delivers R-8 insulated flex duct performance in a 16-inch diameter, 25-foot length. It is UL Listed, built with a patented airtight inner core, and meets major national and regional building code standards for Class 1 air duct installations.

Product Information

Standard Information

• Brand: GRAY FLEX
• Manufacturer Part Number: 16-4GF-8_BAG

Technical Specifications

• Inside Diameter: 16 inches
• Flex Length: 25 feet
• R-Value: R8
• Insulation Thickness: Minimum 2 and 5/8 inches
• Jacket Color: Silver
• Jacket Material: Scrim Reinforced Metalized Polyester Vapor Barrier
• Core Material: Exclusive Patented Inner Core
• Flex Type: Insulated
• Maximum Air Flow: 5,500 FPM
• Maximum Pressure: 10 inches positive, 3/4 inches W.G. negative
• Operating Temperature Range: -20F to 250F (-28.8C to 121.1C)
• Fire Rating: Maximum flame spread 25, maximum smoke developed 50
• Approvals: UL Listed
• Compliance: UL 181, SBCC, NFPA 90A and 90B, HUD 515-2.1, BOCA, ACCA, ADC, ETL
• Vapor Transmission: Jacket only 0.1 (max 0.3) perms per ASTM C96A
• Country of Origin: USA
• Package Type: Bag
• Weight: 35 pounds
• UPC: 687410304333