Structure of the Building Trades Department A.F. of L. of Greater Pittsburgh and Vicinity in 1908:
(source:  Iron City Trades Journal, Sept. 4, 1908)

Plasterers	Slate, Tile and Composition Roofers	Marble Setters and Helpers
Plumbers	Elevator Constructors	Housesmiths
Painters, Paper Hangers and Decorators	Electricians	Mosaic Workers
Building Laborers and Hod Carriers	Steam Fitters and Helpers	Wood, Wire and Metal Lathers
Sheet Metal Workers	Tile Layers and Helpers	Hoisting Engineers