Southwark Metal 21_18X8 Trunk Duct End Cap 18x8

Product Description

The SOUTHWARK METAL 21_18X8 is a sheet metal trunk duct end cap sized at 18 inches by 8 inches, fabricated from hot dip galvanized steel. It is designed to close off the open end of a rectangular trunk duct in forced-air HVAC distribution systems, preventing conditioned air from escaping at duct terminations. The hot dip galvanized finish provides corrosion resistance suited to both conditioned and unconditioned spaces. Licensed sheet metal workers and HVAC installers use this fitting during system commissioning or when reconfiguring duct layouts to cap unused trunk runs.

This end cap is used in residential and light commercial forced-air systems wherever a rectangular trunk duct requires termination. It is appropriate for new construction, retrofit, and duct modification work on supply or return trunk runs measuring 18 inches by 8 inches. Installation typically follows SMACNA and ACCA duct construction standards, making it compatible with work performed under standard mechanical codes.

Key Features

• Hot dip galvanized steel construction for corrosion resistance in HVAC duct applications
• Sized to fit 18-inch by 8-inch rectangular trunk duct openings
• Trunk-type fitting for forced-air supply or return duct systems
• Fabricated to ACCA and SMACNA applicable standards
• Closes off unused or terminal trunk duct ends to maintain system static pressure

Compatibility

Designed as an OEM-style sheet metal fitting for rectangular trunk duct systems measuring 18 inches by 8 inches, built and installed in accordance with SMACNA and ACCA duct construction standards.

Installation Notes

Installation is performed by licensed sheet metal workers or HVAC technicians. Power down the air handling unit and verify the system is de-energized before working inside or at the duct. Secure the end cap using sheet metal screws and seal all joints with UL 181-listed mastic or foil tape per applicable mechanical code requirements. Follow local mechanical codes and SMACNA guidelines for fastener spacing and sealing.

Technical Specifications

• Material: Hot Dip Galvanized Steel
• Size: 18 inches x 8 inches
• Type: Trunk
• Applicable Standards: ACCA, SMACNA

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: 21_18X8