Understanding the Trades

The Talent Behind our Mechanical Systems

Complex systems of pipe and ductwork lie beneath our floors and behind our walls. It is these very systems that make buildings comfortable for us to live in. Mechanical systems, comprised primarily of plumbing, HVAC, and refrigeration, are the result of the efforts of three skilled trades: pipefitters, plumbers, and sheet metal workers. Each trade specializes in one area of mechanical systems but it takes the coordination of all three skills to create the safe and comfortable environments we live, learn, and work in. For those not familiar with the trades, it can be difficult to keep them all straight. Below, is a brief explanation of each trade’s primary role in the creation of mechanical systems.


Pipefitters work on hydronic (heating and cooling) systems, steam systems and refrigeration systems. They install and maintain the systems of piping that are focused on the “energy” of a building. Pipefitters build the systems that transport, steam, gas, and chemicals and much of their work involves soldering, welding, and mechanical joints.


Plumbers work on waste, ventilation, domestic water, and potable water (tap water). They often spend a lot of time on soldering and mechanical fittings. Typically, they work on lower pressure pipes and fixtures for transporting wastewater and freshwater, as well as rain water systems. These are the systems focused on the “health” of a building.

Sheet Metal Worker

Sheet Metal Workers also referred to as “Tinners,” fabricate and/or install ducting and venting systems used for ventilation, along with heating and cooling (air conditioning). They weld and mechanically assemble sheets of metal to create and then install the air transfer systems based on blueprints and plan layout specifications.