The barn owl trust a leading authority on barn owls recommends increasing their nest box dimensions by 50 for the american barn owl equating to a floor dimension of 30 x 24 5 ft2 and a minimum of 10 ft3 for a box that is 24 deep.
Barn owl trust nest box plans.
Climbing jumping young birds can get from the platform onto the roof of the box and ideally onto other nearby perching places.
The dimensions given on the owl box diagram below are the minimum required size.
Front back side side floor roof exercise platform please don t use tropical hardwood.
8 x 4 sheet pressure treated 9mm fsc plywood approx.
Barn owl nestbox for a tree cutting plan.
520mm or 20 5 left over.
For any barn owl nestbox less than 700mm deep an exercise landing platform below the entrance hole is vital for the safety of young fledglings.
Or you can simply buy a barn owl trust nestbox for inside a building.
The ideal size for barn owl boxes is 1m 2 floor area x 1m depth but such big boxes are generally impractical.
Or 5 x 5 distance from top of box to top of hole 50mm or 2.