Southwark Metal 23_18X8 Trunk Duct Collar 18x8 Offset

Product Description

The SOUTHWARK METAL 23_18X8 is a rectangular sheet metal trunk duct collar designed for starting takeoff applications in forced-air HVAC duct systems. Fabricated from hot dip galvanized steel, this collar provides a durable, corrosion-resistant connection point where branch ducts transition off a main trunk. The offset body pattern accommodates spatial constraints common in tight mechanical rooms and attic installations. Licensed HVAC sheet metal technicians and duct installers use this fitting to establish clean, low-leakage connections that meet ACCA and SMACNA standards for residential and light commercial ductwork.

This collar is suited for rectangular duct trunk systems in residential and light commercial forced-air installations. The starting collar configuration makes it appropriate for new duct trunk assemblies where a branch run originates directly from the main supply plenum or trunk line. The 18-inch by 8-inch sizing fits standard duct dimensions used in common HVAC layouts. Installers working on new construction or duct replacement projects will find this fitting compatible with typical galvanized rectangular duct systems built to SMACNA duct construction standards.

Key Features

• Hot dip galvanized steel construction for corrosion resistance in humid and unconditioned-space environments
• Offset body pattern allows clearance adjustments in confined or obstructed installation areas
• Starting collar design establishes branch takeoff points directly on rectangular trunk duct
• Rectangular profile matches standard rectangular duct dimensions for consistent, low-leakage fitment
• Meets ACCA and SMACNA applicable standards for forced-air duct system fabrication

Compatibility

Designed as an OEM-style sheet metal fitting for use with standard rectangular galvanized trunk duct systems in residential and light commercial HVAC applications.

Installation Notes

Installation should be performed by a licensed HVAC technician or qualified sheet metal installer following SMACNA duct construction guidelines. Shut down the air handling unit and confirm the system is de-energized before cutting into existing ductwork or securing the collar to the trunk. Secure the collar with sheet metal screws and seal all joints with UL 181-rated mastic or foil tape per local mechanical code requirements. Verify fitting orientation and offset direction before final fastening to avoid rework.

Technical Specifications

• Material: Hot Dip Galvanized Steel
• Size: 18 inches Length x 8 inches Width
• Body Pattern: Offset
• Type: Starting, Rectangular
• Applicable Standards: ACCA, SMACNA

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: 23_18X8