The ideal size for barn owl boxes is 1m 2 floor area x 1m depth but such big boxes are generally impractical.
Barn owl trust nest box plans.
A full 1 metre 3ft from the bottom of the entrance hole to the bottom of the box and with a floor area of at least 1 metre x 1 metre.
Front back side side floor roof exercise platform please don t use tropical hardwood.
Our design is 11 ft3 with with nearly 6 ft2 of floor space.
Or 5 x 5 distance from top of box to top of hole 50mm or 2.
520mm or 20 5 left over.
Barn owl nestbox for a tree cutting plan.
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.
Climbing jumping young birds can get from the platform onto the roof of the box and ideally onto other nearby perching places.
Or you can simply buy a barn owl trust nestbox for inside a building.
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.