Discussions about merging the various building industry unions had begun by the 1930s, and in 1934, the New South Wales state carpenters' and bricklayers' unions merged as the Building Workers' Industrial Union, with approaches also being made to the plasterers', painters' and labourers' unions. In 1943, the issue of amalgamation on a broader scale emerged again. The federal Amalgamated Society of Carpenters and Joiners sought to expand its coverage to workers across the entire building industry, and changed its name to the '''Building Workers' Industrial Union''', with a number of state-level unions merging into the union. In the same year, the New South Wales branch affiliated with the
Australian Labor Party for the first time, breaking from the Carpenters' and Joiners' historical non-affiliation. The union suffered a setback in 1944 when the amalgamation of the Queensland state Carpenters' and Joiners' with Painters' and Decorators' Union and the Queensland branch of the
Builders Labourers Federation to form a Queensland state branch of the BWIU was blocked in court after a challenge from the
Australian Workers' Union and other rival unions. A second attempt was made later that year to merely rename the state Carpenters' and Joiners' Union as the BWIU, as had occurred federally, but was also blocked in court; the state union also lost on appeal the next year. The New South Wales branch was headed by Communist leadership through much of
World War II, and faced an ongoing dispute over their coverage on the wharves with the newer and more conservative rival
Ship Joiners' Society. ==Deregistration==