For the purpose of the Washington state public works law, chapter 39.12 RCW, roofers apply and install any and all types of roofing materials, other than sheet metal. The work of roofers includes, but is not limited to:

(1) The installation of slate and tile and all substitute materials taking the place of slate and tile, with necessary metal flashing to make water-tight.

All cementing in, on or around slate and tile roofs.

All laying of felt or paper beneath the slate and tile.

All dressing, punching and cutting of all roof slate or tile either by hand or machinery.

(2) The installation of all forms of plastic, slate, slag, gravel; asphalt and composition roofing; rock asphalt mastic when used for damp and waterproofing; prepared paper; compressed paper, and chemically prepared paper with or without coating.

The installation of all damp resisting preparations when applied on roofs with mop, three-knot brush, roller, swab or spray system.

(3) The installation of all forms of elastomeric and/or plastic (elasto-plastic) roofing systems, both sheet and liquid applied, whether single-ply or multi-ply.

All types of aggregates, blocks, bricks or stones used to ballast these elasto-plastic systems.

All types of aggregates used as a ballast for inverted roofing membrane assembly, or roof of similar construction where the insulation is laid over the roofing membrane.

All sealing and caulking of seams and joints on these elasto-plastic systems to insure water-tightness.

All liquid-type elasto-plastic preparation for roofing, damp or waterproofing when applied with a squeegee, trowel, roller or spray equipment.

All sheet-type elasto-plastic systems, whether single or multi-ply, for waterproofing.

All priming of surfaces to be roofed, damp or waterproofed, whether done by roller, mop, swab, three-knot brush, or spray systems.

All types of preformed panels used in waterproofing.

(4) The application of all types of spray-in-place foams such as urethane or polyurethane, and the coatings that are applied over them.

(5) The application of roof insulation, when the insulation material is applied as an integral part of the roofing system, whether the insulation material is applied as the first, last or any other layer in between.

(6) The handling, hoisting and storing of all roofing, damp and waterproofing materials.

(7) The tear-off and/or removal of any type of roofing, including roofing materials containing asbestos, all spudding, sweeping, vacuuming and/or cleanup of any and all areas of any type where a roof is to be relayed, and all other cleanup required in connection with roofing work.