Thermaflex 56312000002 Flex-vent R-8 Insulated Flex Duct 12in X 25ft

Product Description

The THERMAFLEX 56312000002 is a KM-series R-8 insulated flexible air duct designed for low- to medium-pressure HVAC distribution systems. It measures 12 inches in diameter and comes in a 25-foot length. The inner core is a smooth polyester film supported by a heavy-gauge, corrosion-resistant steel wire helix. That helix maintains the circular cross-section under compression and bending. A thick blanket of fiberglass insulation wraps the core to deliver an R-8 thermal rating. A bi-directional reinforced metallized vapor barrier forms the outer jacket, resisting moisture infiltration without unraveling at seams or cut ends. HVAC technicians and sheet metal installers use this duct in residential and light commercial air distribution branches.

This flexible duct is suited for residential forced-air systems and light commercial HVAC installations where flexible branch runs connect rigid trunk lines or air handlers to supply registers. The 12-inch diameter accommodates higher-volume branch runs typical of large residential zones or small commercial spaces. The R-8 insulation rating meets requirements commonly specified for attic, crawlspace, and unconditioned-space installations under energy codes. The reinforced outer vapor barrier makes it appropriate for humid or semi-conditioned environments where moisture control is critical.

Key Features

• R-8 fiberglass insulation blanket reduces heat gain and loss in unconditioned spaces
• Smooth polyester film inner core promotes low air resistance and easy airflow in low- to medium-pressure systems
• Heavy-gauge corrosion-resistant steel wire helix supports the inner core and maintains duct shape under bending
• Bi-directional reinforced metallized outer vapor barrier resists moisture and will not unravel at cut edges
• 12-inch diameter by 25-foot length suits high-volume residential branch runs and light commercial supply lines

Compatibility

Designed as an OEM-style replacement and new-installation flexible duct for residential and light commercial forced-air HVAC systems requiring a 12-inch insulated flex duct with an R-8 thermal rating.

Installation Notes

Installation should be performed by a licensed HVAC technician in accordance with applicable mechanical codes, including SMACNA flexible duct installation guidelines and local energy code requirements. Shut down and de-energize the air handling unit before connecting or securing duct ends. Secure each end with approved clamps or draw bands and seal with listed mastic or metal tape rated for flexible duct. Avoid sharp bends that compress the inner core, as restricted cross-sections increase static pressure and reduce system airflow.