Atco 031-R8_8X50FT R8 Flexible Air Duct 8 in 50 Ft Class 1

Product Description

The ATCO RUBBER PRODUCTS 031-R8_8X50FT is an R8-insulated, Class 1 flexible air duct designed for residential and commercial HVAC distribution systems. Measuring 8 inches in diameter and 50 feet in length, it delivers a maximum air velocity rating of 5000 FPM and handles up to 6 inches WG positive pressure per UL 181. The duct features an air-tight 2-ply polyester inner core that prevents fiberglass erosion into the airstream, a thick blanket fiberglass insulation layer for high thermal efficiency, and a tough silver metalized polyester outer jacket rated for tear and puncture resistance. Plain end terminations allow straightforward field connections. Licensed HVAC technicians and sheet metal mechanics are the primary installers.

This flexible duct is suited for supply-air branch runs in residential forced-air systems and light commercial HVAC applications where a Class 1, UL 181-listed product is required. The R8 insulation value meets or exceeds energy code requirements in most jurisdictions, making it appropriate for unconditioned attic, crawlspace, and plenum-adjacent installations. The encapsulated wire helix resists unraveling when the duct is cut to length, supporting faster installation in tight spaces. Compatible with standard round sheet metal collars and flex duct connectors in the 8-inch nominal size range.

Key Features

• R8 thick blanket fiberglass insulation for superior thermal performance and energy efficiency
• Air-tight 2-ply polyester inner core eliminates fiberglass erosion into the conditioned airstream
• Encapsulated wire helix prevents unraveling when cut, enabling fast, clean field trimming
• Silver metalized polyester jacket resists tearing and puncture for long service life
• Rated 5000 FPM air velocity and 6 inches WG positive pressure per UL 181
• Temperature range of -20 to 180 degrees F continuous, -20 to 250 degrees F intermittent
• Listed to UL 181, NFPA 90A and 90B, IMC, IRC, UMC 10-1, HUD, and ASTM C-518

Compatibility

Designed as an OEM-style Class 1 flexible duct replacement or new-installation product for 8-inch nominal round duct connections in residential and light commercial forced-air HVAC systems.

Installation Notes

Installation should be performed by a licensed HVAC technician or sheet metal mechanic in accordance with IMC, IRC, and local mechanical code requirements. Shut down and de-energize the air-handling unit before connecting or disconnecting duct sections. Secure both ends with listed duct straps or clamps and seal all connections with UL 181B-listed mastic or tape as required by the applicable mechanical code. Avoid sharp bends that reduce the interior diameter, as this increases static pressure loss and restricts airflow.

Technical Specifications

• Diameter: 8 inches
• Length: 50 feet
• Insulation Type: Thick Blanket Fiberglass
• Insulation Value: R8
• Core Material: 2-Ply Polyester
• Jacket Material: Metalized Polyester
• Air Velocity Rating: 5000 FPM
• Rated Positive Pressure: 6 inches WG per UL 181
• Rated Negative Pressure: 1 inch WG per UL 181
• Temperature Rating: -20 to 180 degrees F continuous, -20 to 250 degrees F intermittent
• Flame Spread Index: 25 maximum
• Smoke Developed Index: 50 maximum
• Duct Type: Class 1, Insulated, Flexible, Plain End
• Applicable Standards: UL 181, NFPA 90A and 90B, IMC, IRC, UMC 10-1, HUD, ASTM C-518

Standard Information

• Brand: ATCO RUBBER PRODUCTS
• Manufacturer Part Number: 031-R8_8X50FT