Plumbers & Steamfitters UA Local 400 is comprised of approximately 2,000 members serving eighteen counties in Northeast Wisconsin. We are a local union that is affiliated with the United Association of Plumbers & Pipefitters, comprised of approximately 345,000 members across the US and Canada. Our main purpose is to provide training for our members and qualified manpower to our 105 signatory contractors for all aspects of the plumbing, pipe fitting, HVACR service, and pipe fabrication industries.