- Plumbing, heating, air-conditioning (4)
- Painting and paper hanging (3)
- Electrical work (1)
- Masonry and other stonework (3)
- Plastering, drywall, and insulation (1)
- Carpentry work (2)
- Water well drilling (3)
- Glass and glazing work (1)
- Excavation work (3)
- Installing building equipment (1)
- Special trade contractors, nec (3)
