Suitable Nestbox Size: 24 inches tall. No perches at the entrance holes as they would aid predators. Line the floor with some wood chips.
Floor Dimensions: 12 ” x 12″ with ventilation holes (suggested 5). Although some experts disagree with the notion that ventilation openings are needed at all. Please refer to this article for further information. This may also depend on location of nest box, exposure to direct sun as well as material used to build the nest box.
Entrance Hole: oval shape, 5 ” wide x 5″ high, located about 20″ above the floor.
Roof: Hinged, secured with shutter hooks. Sloped down, overlapping on the sides and the front reduces exposure to rain and makes it more difficult for predators to get to the chicks or eggs.
Hardware: Best to use corrosion resistant, stainless steel and dichromate plated screws
Material to be used: Red Cedar (more durable than other wood material), rough cut boards or exterior-grade plywood at least 1/2″ thick. Unpainted.
Predator Guard: An inverted metal cone attached below the nextbox will provide some protection against predators
Mount 10 feet or higher on a tree or a post; a few feet lower to the ground if the post is in standing water.
Close to bodies of water (lakes or rivers) or marshes; best placed facing water or in standing water to reduce the risk of predation