Dimensions: overall 25 x 11.25 x 11, floor 7 x 7.5, entrance 2.5, center entrance to floor 15. It’s best to position the nest box on a tree or pole 6 to 12 feet high, preferably a pole with a squirrel and predator baffle. Face the entrance south or east in a shaded open wooded area in town or in a rural setting, and make sure there is an open flyway to and from the nest box. Tip - for attracting woodpeckers to a nest box fill the box about 1/2 way full of wood shavings (not sawdust). Excavating the chips is a natural instinct and found desirable for woodpeckers.