Quietflex 8516 Uv-inhibited Flex Duct 8 Inch 25 Foot

Product Description

The QUIETFLEX 8516 is a Series 54 UV-inhibited flexible duct designed for residential and light commercial HVAC distribution systems. The duct features a metallic polyester vapor barrier jacket with a rip-stop scrim reinforcement that resists tearing during handling and installation. The insulated core uses Johns Manville formaldehyde-free fiberglass insulation and carries GREENGUARD Certification. A galvanized metal inner core is oversized to allow easy connection to collars and register boxes. This unit ships in an 8-inch diameter by 25-foot length and is packaged in weather-resistant packaging for jobsite storage.

This flex duct is suited for supply and return air applications in ducted forced-air systems. The UV-inhibited jacket makes it appropriate for installations where the duct may be exposed to sunlight, such as attic runs or crawlspace work in warmer climates. The oversized core simplifies fitting onto standard collars without the need to stretch or force the inner liner. HVAC technicians and sheet metal contractors are the primary installers on both new construction and replacement duct work.

Key Features

• Rip-stop scrim reinforcement on metallic polyester vapor barrier jacket resists tearing during installation
• Johns Manville formaldehyde-free fiberglass insulation — GREENGUARD Certified
• Galvanized metal core reinforcing for structural integrity and airflow maintenance
• Oversized inner core fits standard collars and register boxes without stretching
• UV-inhibited jacket rated for exposed or semi-exposed duct runs
• Meets HUD/FHA standards 515.2.1 Paragraph B, NFPA 90A and 90B, BOCA, and City of Chicago requirements

Compatibility

Designed as an OEM-style flexible duct for use with standard 8-inch HVAC collars and register boxes in residential and light commercial forced-air distribution systems. Meets most federal, state, and local codes and standards per manufacturer documentation.

Installation Notes

Installation should be performed by a licensed HVAC technician or qualified sheet metal contractor in accordance with local mechanical codes and NFPA 90A or 90B as applicable. Power down the air handler and close the supply shutoff before cutting into existing ductwork. Secure both ends of the flex duct with approved sheet metal screws and UL-listed duct tape or mastic sealant — do not rely on tape alone at the collar connection. Avoid excessive bends or compression of the liner, which reduces airflow and system efficiency.

Technical Specifications

• Diameter: 8 inches
• Length: 25 feet
• Series: 54
• Type: UV-Inhibited
• Jacket: Metallic polyester vapor barrier with rip-stop scrim
• Insulation: Johns Manville formaldehyde-free fiberglass
• Inner Core: Galvanized metal reinforcing
• Certifications: GREENGUARD Certified, NFPA 90A, NFPA 90B, HUD/FHA 515.2.1 Paragraph B, BOCA

Standard Information

• Brand: QUIETFLEX
• Manufacturer Part Number: 8516