The Sheet Metal Workers' International Association represented about 150,000 members in 185 local unions in the United States and Canada.
The union was founded on January 25, 1888, in Toledo, Ohio, as the Tin, Sheet Iron and Cornice Workers' International Association.
The Sheet Metal Workers had organized thousands of railway locomotive fabricators nationwide, but now the plumbers' union was arguing that it had jurisdiction over the piping work that went into building these engines.
In 1921, the federated union disbanded, but the Amalgamated Sheet Metal Workers won substantial jurisdictional concessions from the plumbers.
Finally, on April 26, 1955, the National Mediation Board reaffirmed Amalgamated Sheet Metal Worker jurisdiction over plumbing and pipefitting work in the railroad industry.
The United Brotherhood of Carpenters and Joiners of America claimed jurisdiction over trim and moldings, which had previously been made of wood.
But the Amalgamated Sheet Metal Workers demanded that the Building Trades Department (BTD) of the AFL issue a ruling.
The carpenters, then the second-largest union in the AFL, withdrew from the Building Trades and initiated a series of jurisdictional strikes against the Amalgamated Sheet Metal Workers at job sites nationwide.
But the pressure by the much larger carpenters' union proved too great, and the Amalgamated Sheet Metal Workers conceded jurisdiction over interior work in 1926.
In the spring of 1927, members of Local 206 in San Diego, California, build structural reinforcements for Charles Lindbergh's aircraft, "The Spirit of St.
[4] In 1993, Edward J. Carlough resigned as president of the Sheet Metal Workers after union members strongly criticized his lavish lifestyle and excessive spending.
[9] The merger between the SMWIA and the United Transportation Union (UTU) was finalized at the SMART First General Convention held in Las Vegas, Nevada the week of August 11–15, 2014.
Sheet Metal Workers Union was the United States' 27th largest donor to federal political campaigns and committees, having contributed over $51.8 million since 1989, over 90% of which went to the Democratic Party and other liberal groups.