Thermaflex 56309000002 Insulated Flex Duct R-8 9in X 25ft

Product Description

The THERMAFLEX 56309000002 is an R-8 insulated flexible duct designed for residential and light commercial HVAC air distribution systems. Constructed with a silver jacket exterior, it provides a high level of thermal insulation performance at R-8, reducing heat gain and loss between the air handler and the supply register. The 9-inch diameter and 25-foot length make it well suited for trunk-to-register runs in attic, crawlspace, and conditioned-space installations. HVAC technicians use flex duct as a key component in achieving efficient, code-compliant duct systems.

This flex duct is used in forced-air heating and cooling systems where flexible runs are needed to connect rigid ductwork or plenums to supply boots and registers. Its 25-foot length accommodates most standard residential runs without splicing, and the 9-inch diameter supports higher-volume supply branches. The silver jacket is suited for attic installations where reflective facing may contribute to thermal performance in unconditioned spaces.

Key Features

• R-8 insulation rating for high thermal efficiency in supply air distribution
• 9-inch inner diameter supports higher-volume supply branch runs
• 25-foot length reduces the need for mid-run splices or couplings
• Silver jacket exterior suitable for attic and exposed installations
• Flexible construction allows routing around obstructions and framing members

Compatibility

Designed as an OEM-style replacement or new-installation flex duct for residential and light commercial forced-air HVAC duct systems using 9-inch diameter fittings, collars, and boots.

Installation Notes

Insulated flex duct is installed by licensed HVAC technicians in accordance with ACCA Manual D and applicable local mechanical codes. Power down the air handler and seal the system before cutting into existing ductwork. Avoid sharp bends or compressed runs, as restrictions increase static pressure and reduce airflow; maintain bend radii per SMACNA and manufacturer guidelines. Secure connections at both ends with approved drawbands and mastic or UL 181-rated tape — never use standard cloth duct tape alone on flex duct connections.