- Five pieces an outdoor-safe wood, such as cedar
- Exterior primer
- Exterior latex paint
- One 6-foot piano hinge (with included screws)
- Exterior-grade wood glue
- 3 Ikea Ekby Valter shelf brackets (with the top nubs removed)
- Three 10-inch piano hinges with an open width of 1 1/2 inches (with included screws)
- Screw gun
- 9 exterior screws (masonry and cinder block facades require appropriate screws and anchors)
Have wood cut at a hardware store: one 6-foot-by-2 3/8-inch-by-1-inch board; one 6-foot-by-10 1/2-inch-by-1-inch board; and three 10-by-2 1/2-inch-by-3/4-inch vertical buttresses. Paint each piece of wood with primer, and let dry. Then paint, and let dry.
Assemble the under mount: Connect 6-foot-by-2 3/8-inch board to the back of 6-foot-by-10 1/2-inch board using drill and 6-foot hinge. Glue vertical buttresses to bottom of smaller board: Place 1 in the center, and others 3 3/4 inches in from each end.
Drill 2 screws into smaller plank and each buttress from above (predrill holes to prevent wood from splitting).
Connect brackets to buttresses using 10-inch hinges, and drill.
Attach under mount to house using exterior screws, placing 3 on each buttress.