This minor group comprises plumbers, steamfitters, pipefitters, sprinkler system installers, and gas fitters. They are employed by plumbing contractors; maintenance departments of factories, plants and similar establishments; pipefitting and sprinkler system contractors; and gas utility and gas servicing companies; or they may be self-employed.

This minor group comprises carpenters and cabinetmakers. They are employed by construction companies; carpentry and cabinetmaking contractors; maintenance departments of factories, plants and other establishments; and furniture manufacturing and repair companies; or they may be self-employed.

This minor group comprises bricklayers and insulators. They are employed by construction companies and bricklaying contractors; or they may be self-employed.