Plumbers and Steamfitters Local 21 is a Craft Union representing members employed in the construction industry. We work on everything from single family homes to nuclear power plants. From high rise buildings to high purity installations, schools, hospitals, and factories. From large industrial and commercial facilities to residential homes and developments. If its piping work, we do it! But it's so much more than that. Installation, service, estimation, Computer Aided Drafting (CAD), supervision and management are all provided by Local 21 and our signatory contractors.