Not to be confused with someone who rides the roof of a train, or Atapper.A roofer or roof mechanic is a construction worker who specializes in roof construction. Roofers concentrate on the application of materials that waterproof and/or weatherproof buildings, designed material—as a substrate for the roofing materials to be installed on, the rafters, beams, and trusses are the frame or skeleton for the roof to be built upon.