Building a barn owl box (2)

The box is complete! The photos below record the process of construction as it happened...

The front with cut-outs. Ideally the piece cut out for inspection panel could be used for the panel itself, but unless you're very neat and the saw blade very fine then the piece cut out will not fit tightly enough. I had to discard it and cut a new one. Not a problem as there's plenty remaining from the sheet.

The front with top and side battens. The length of the side battens is such that there is 2cm beneath the base when fitted.

The back with battens in place. The centre batten is to provide strengthening - the box will be attached to a tree via a substantial batten (1.5" x 3") which is bolted to the back of the box.

The side battens deliberately overlap the top corners of the inspection hatch. Along with a retaining piece on the lower edge this is what's intended to stop the panel falling into the box. I decided to overlap the panel all the way so there would be no light leakage into the box...

... the edging was done using pieces cut from the remaining plywood. The side pieces are not yet in place here.

The back with sides attached.

The front in place. It's flush at the bottom and recessed 4" at the top.

With top attached.

A view of the bottom. The base is left until the end to allow easy access for fitting the inspection panel.

The shelf in place. A couple of wedges help to make it firm...

...as shown here.

The back of the inspection panel. The original plans use some pieces of wood on the outside of the front to hold the panel in place, but I thought they might be liable to getting wet and rotting (because the end-grain is upright) and so put some lugs on the inside instead.

The lugs are just bits of waste plywood that fit over the lip of the hatch opening.

The base with drain holes. The base needs to be planed to fit, including bevelling the ends slightly to match the slope of the sides.

The box completed! The battens on the back (and where they fix to the sides) are glued as well as screwed since all the weight of the box is carried here. Use glue sparingly (wood glue, waterproof) so it doesn't spread inside the box.

The box will be treated on the outside (only) with a few coats of water-based preservative. I use Cuprinol Ultimate Green, partly due to availability and partly a personal choice of colour. It's one of the expensive 5-year treatments but hopefully worth it. Solvent-based preservatives are generally more effective but definitely not recommended for bird boxes.

Now I'm just waiting for some roofing felt to put on the top....

Eventually it turned up. The finished box:

That's it!

Building a barn owl box

I don't remember what gave me the idea of building owl nest boxes. Maybe it was after visiting a rather sad owl sanctuary in the west country which my wife Jill was really uncomfortable with (although I was able to get some good owl photos), possibly this made me realise that we no longer have owls around where I live. Anyway, I decided to make a Tawny owl box (Dutch letterbox design) and the local council kindly agreed to put it in a nearby field that they own. That led to my being asked if I'd like to made some Barn owl boxes for them, and so I agreed.

I looked around on the Internet for a suitable design. The simplest type is the A-frame, but I don't really like this because the bottom corners seem wasted space, unusable by the owls and places where all manner of crud will accumulate. The Barn Owl Trust has what looks to be a well designed box and that's what I'm making. As well as providing plans, their website also contains step-by-step pictures of construction which are very helpful but probably don't contain everything you need to know. At least one thing not covered is how to lay out and cut the pieces needed from a single sheet of plywood, and so I've had to do this myself as shown below.

Cut all the pieces out. I normally like to use a panel saw for woodworking but I decided a jigsaw would give a cleaner (and thinner) cut. The cut edges can be cleaned up with a plane. Eventually some of the edges will need to be bevelled a bit (top of sides, front and back, and the ends of the base. This will be evident when you assemble the box.


The notes on the diagram above give a few tips, including how to cut out the front and back trapezoids without resorting to Pythogras!