Flexduct 1420 Flex Air Duct 14 in 25 Ft R4.2 Fiberglass

Product Description

The FLEXDUCT 1420 is a UV-inhibited fiberglass flexible air duct rated at R4.2 thermal insulation. Measuring 14 inches in diameter and 25 feet in length, it is designed for use in residential and light commercial HVAC distribution systems. The black outer jacket resists UV degradation, making it suitable for installations where the duct may be exposed to sunlight during handling or in partially exposed spaces. HVAC technicians and sheet metal installers use this product to connect air handlers, plenums, and branch takeoffs to diffusers and grilles. The fiberglass insulation wrap maintains the R4.2 thermal rating required by many residential energy codes.

This flex duct is used in forced-air heating and cooling systems where flexible connections are needed to reduce vibration transmission or navigate around structural obstructions. Typical applications include trunk-to-register runs in attics, crawlspaces, and conditioned mechanical rooms. The 25-foot length accommodates most residential branch runs without a splice. Installers working on new construction and retrofit projects use this duct to complete low-velocity supply and return air distribution.

Key Features

• R4.2 fiberglass insulation rating meets common residential energy code minimums for duct insulation
• UV-inhibited black outer jacket reduces jacket degradation during outdoor exposure or attic storage
• 14-inch diameter fits standard 14-inch round collars, plenums, and takeoff fittings
• 25-foot length reduces the need for mid-run splices on typical residential branch runs
• Flexible construction allows routing around framing members and mechanical obstructions

Compatibility

Designed as a standard R4.2 flexible air duct replacement and new-installation product compatible with 14-inch round duct collars, takeoffs, and fittings used in residential and light commercial forced-air HVAC systems.

Installation Notes

Installation should be performed by a licensed HVAC technician in accordance with SMACNA flexible duct installation guidelines and applicable local mechanical codes. Power down and lockout the air handling unit before making duct connections. Avoid sharp bends that reduce the duct diameter and restrict airflow; maintain bend radii per manufacturer and code requirements. Secure all connections with approved draw bands and mastic or code-compliant tape — never use standard cloth duct tape as the sole sealant.

Technical Specifications

• Diameter: 14 inches
• Length: 25 feet
• Insulation R-Value: R4.2
• Insulation Material: Fiberglass
• Outer Jacket: UV-inhibited black
• Package Dimensions (L x W x H): 16.5 inches

Standard Information

• Brand: FLEXDUCT
• Manufacturer Part Number: 1420