Roofing contractors use manual and motorized hoists to load roofing materials. Hoist lines can be attached to a pallet for lifting bundles of shingles or rolls of roofing paper. Ladder hoists are relatively inexpensive but pose safety hazards. An A-frame hoist attached to the roof reduces safety concerns. Block and tackle rigging provides a mechanical advantage for the loaders.
Things You'll Need
- 2-inch-by-4-inch utility lumber
- Circular saw
- Electric drill
- 1/4-inch drill bit
- 1/8-inch drill bit
- 6-inch machine bolts with nuts and washers
- Socket and ratchet
- Threaded lag hook
- 3-inch lag screws with washers
- 1/2-inch braided rope
- 4-inch pulleys
Cut three lengths of 2-inch-by-4-inch utility lumber to make a triangle A-frame for a pitched roof hoist. The base should be 10 feet long, and the tip of the triangle should be 15 feet from the center point of the base.
Align the pieces of the triangle on edge. Use an electric drill with a 1/4-inch drill bit to make pilot holes for machine bolts at the corners of the triangle. Insert a 6-inch long machine bolt into each pilot hole. Put washers and nuts on the bolts and tighten the nuts with a socket and ratchet.
Drill a 1/8-inch pilot hole near the tip of the triangle. Insert a threaded lag hook in the pilot hole as a pulley stay. Twist the hook tight, using a screwdriver, in the loop of the hook.
Cut a length of utility lumber to fit inside the base of the triangle from end to end. Drill 1/8-inch pilot holes at 24-inch intervals on the face of the piece. Measure 10 feet from the edge of the roof and position the piece parallel to the roof edge at this location. Insert 1/4-inch lag screws in each pilot hole and attach the piece to the roof sheathing with a socket and ratchet.
Cut a piece of utility lumber 6 feet long as a base for the A-frame support arms. Drill pilot holes in the face of the piece. Align the center of the base with the center of the previously installed 10-foot piece. Position the base 36 inches from the roof edge and parallel. Attach the base to the roof sheathing with lag screws.
Attach the base of the triangle A-frame to the ends of the 10-foot piece with lag screws. Have assistants hold the A-frame level so it extends over the roof edge. Cut two support arms that attach to each end of the 6-foot base and the sides of the A-frame. Attach the arms with lag screws.
Measure the distance from the ground to the point of the A-frame. Cut a length of 1/2-inch braided rope three times this measurement. Rig a gun tackle, using two, 4-inch pulleys and the braided rope. Hook one of the pulleys to the hook stay on the point of the A-frame.
Make a rope truss for the loading pallet, using 1/2-inch braided rope. The truss should attach to each corner of the pallet and extend above the pallet enough to load materials. Hook the lower pulley onto the top of the truss. Pull the tag end of the gun tackle rigging rope to hoist the pallet above the edge of the roof.