Owl nest box plans

A female Flammulated Owl looks out of a nest box. This box was made with a plan similar to the one presented below; bark slabs were added for a more natural look at the end.
Many species of small owls–including Flammulated, Northern Saw-whet, Boreal and all the Screech-Owls–will readily nest in a nest box that is properly designed and placed. Here are some plans for a box that all the above species will nest in. Use 3/4″ or 1″ rough plywood; there is no need to paint or stain the box. It’s a good idea to rough up the inside of the front panel on the box (with a few saw strokes) so that the young birds can have an easier time getting out when they’re ready to go. When you’ve built the box, put a couple of handfuls of sawdust or wood-chips in the bottom (owls don’t build their own nest) and nail or screw it to a large tree trunk. The exact height doesn’t matter–simply put it up as high as you can with whatever ladder you have. It’s important that the box be easily accessible for cleaning. Place the box so there is a clear flight path to it; most species would prefer a tree on the edge of or within open woodland. Look into the box once or twice a year at least–preferably once in spring when owls might be using it, and again in the fall when you can clean out any old nest material that other species may have put in there (squirrels, starlings…).
Thanx for posting Dick!
If finished lumber/plywood is used, I suggest scouring or adding some sort of climbing aid on the inside of the box, below the hole. That will help birds climb up to the entrance. The inside of a natural cavity is quite rough.
Yes, thanks for adding that, Mark. I forgot to mention that step. I just run a saw over the inside of the front panel of the box a few times.
Thank you Dick. What are the dimensions of the floor?
8 X 8 inches