What are Sheet Metal Workers?

Sheet Metal Workers—commonly known within the trade as “Tin Knockers”—are highly trained professionals who design, fabricate, install, maintain and service a wide range of sheet metal systems and products. Their expertise is critical to industries such as construction, manufacturing, and HVAC service.

The trade encompasses the full scope of work from blueprint interpretation and precision fabrication in shop settings to installation and maintenance in the field. Typical projects include heating, ventilation, air conditioning and refrigeration (HVAC/R) duct systems and equipment, architectural and structural sheet metal features, outdoor signage, and custom precision-fabricated components.

Many Sheet Metal Workers are proficient across all aspects of the trade, while others choose to specialize in areas such as fabrication, installation, or service. The profession also includes specialized roles such as welding fabricators, Test and Balance technicians who ensure HVAC/R system performance and efficiency, service technicians who diagnose and repair mechanical systems and controls technicians.

Through a combination of technical skill, craftsmanship, and adaptability, Sheet Metal Workers play a vital role in modern construction and infrastructure, ensuring that essential systems function efficiently, reliably, and safely across residential, commercial, and industrial settings.

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