Pigeon hole shelving is another name for a cubby shelving system, where the shelving unit is full of sectioned off cubbies. Making a pigeon hole shelving unit is not very difficult and any do-it-yourselfer will be capable of building one using a small number of tools and some relatively inexpensive materials, mainly plywood, and a few simple tools.
Cut out a 4-foot by 2-foot piece of wood for the back, two 2-foot by 1-foot pieces for the sides and four 4-foot by 1-foot pieces for the top, bottom, middle and cubby sides from a 4-foot by 8-foot sheet of plywood. Use a table saw to cut the wood.
Build a wooden box frame using the two 2-foot by 1-foot sides, the 4-foot by 1-foot top and the 4-foot by 1-foot bottom pieces. To attach the corners of the wooden box frame, drill 3/4-inch screws into the corners of the frame. The frame should measure 2-feet wide by 2-feet tall and 1-foot deep.
Attach the 4-foot by 1-foot middle piece to the inside of the wooden box frame by drilling 3/4-inch nails from the outside of the frame into the edge of the middle piece. This middle piece will act as the shelf of the pigeon hole shelving unit.
Cut the 4-foot by 1-foot cubby side piece into four 1-foot by 1-foot squares.
Insert two cubby side pieces into the box frame on the top shelf and two on the bottom shelf; each piece should be 1 3/4 inches from the sides of the shelves and 1 1/2 inches from each other. Attach the pieces by drilling 3/4-inch screws from the top and bottom of the frame into the edge of the cubby sides.
Attach the 4-foot by 2-foot back piece to one end of the frame to close off the pigeon hole shelving unit on one side.