I have been designing, building and placing nest boxes for American Kestrels for over 30 years, both in Wisconsin and in Colorado.
The nestbox dimenstions that most people use too small...in my opinion.
Therefore, I have a box design that works very well for the birds.
The dimesions are...
Front 11x16
Back 11x22
Top 11x13
Side 11x16
Side 7 x 11 and the lower part 9 x 11. This is the door placed to extract the young for banding and for cleaning the box
Bottom 11 x 9.5
The entracne hole is 3 inches and palced either 1 inch or 1.5 inches from the top fromtof the box.
The door is on the side and a nail is used to keep the door closed. Just drill a hole in the front so that a nail can be used to keep the door closed.
Agreed. We have used 1x12 planks since the 70s. Hawk Mountain's website has a diagram but it's simple enough. The larger space allows 5 birds to stand on the floor instead of on each other. More air circulation as well. Good post