How to set up house for our feathered friends.
Like hunting and gathering, the need to nest is fairly deep rooted. The role of shelter is the same across species-whether bird, dog or human-but the specifications vary even within species, of course. For birds a nest box (or birdhouse) requires specific entrance-hole sizes and minimum interior dimensions, depending on the size of bird you want to attract. Will you attach the box to a tree, pole, fence post or to the side of building? And at what height? Find out how best to accommodate specific feathered friends before you begin. See "For the Birds" on page 23 for insights and guidelines; libraries, bookstores or the Internet can supply more information about the nesting requirements of different species.
I chose to build a nest box for tree swallows-common backyard birds -basing material sizes on the dimensions listed on page 26. However, the step-by-step instructions here can also be used to make nest boxes for other species, adapting them to the requirements listed in the chart.
1. Make a cutting list. If you are building the box for a bird with size requirements different from those of tree swallows, remember to allow for joint overlap so that your interior dimensions are correct: for each joint, include the panel thickness in the width of your outer board.
2. Choose your lumber. Rough lumber is best-it gives fledglings something to climb up when they are ready to fly. Softwood is easier to work with than hardwood, so try to find spruce or pine. If, like me, you choose to use pieces of tongue-and-groove, plane or chisel off any tongues that will be exposed and get in the way of clamping, and then glue and clamp the pieces together to make up the required widths. Alternatively, use 5 feet of dressed 1" x 6"-it comes finished to 3/4" x 5 1/2" so it already matches our dimensions.
3. Lay out all your shapes on the boards. Your box roof will slope up from front to back, so the top of the sides will be laid out on an angle. After you cut this angle for one side, flip the off-cut-your board end-around, and lay it on your first panel. The angles are the same so you just need to mark and cut that second side to length. Cut all your panels out.
4. Bevel the front panel to fit under the roof. To locate depth lines for your planing, use one of the side panels to trace the angle on the sides of your front panel. Do this to both sides of your front panel, and then draw a line across the front of the panel joining the two marks. This line is the lower extent of the bevel. If your front panel is cut too long (high), you'll need to do this for the inside upper edge as well, but it's easier to just cut it to the right height. Then clamp the front panel in the vise (gently, so you don't crush your wood) and plane the bevel along the top, making sure not to go down past your depth lines. You're planing across end-grain so set your plane blade for a shallow cut and work carefully. Planing straight across can cause tear-out at the far side, so before you start, clamp your board (edge side up) in the vise and make a shallow saw-cut along the line.
5. It's time to put a hole in for the bird's front door. The 1 1/2" entrance hole is 1 1/2" below the top of the front panel, so the centre of the hole is 2 1/4" below the top. To lay this out, first find and mark the centre of the panel on its top edge. Use a square to mark a line down the front face of the panel, or find the centre of the bottom edge and join your top and bottom marks with a line. Mark the centre of your hole 2 1/4" down this line from the top. Set your compass to 3/4" and draw a circle centred on the mark. Clamp the panel to the workbench. Use a scrap under it, both to protect the bench and to make a clean drilling exit. Drill the hole using a 1 1/2" bit, or use a small drill bit to put holes around the inside of the perimeter-then unclamp the panel and cut between those with a coping saw or jigsaw. Round and smooth the hole with a round rasp or 80-grit sandpaper wrapped around a pencil.
6. Drill ventilation and drainage holes in the other panels. Stack the two sides, and clamp them onto the workbench and scrap board. Drill two 1/4" ventilation holes 3/4" from the sides and top, back and front, of both side panels. Set those aside. Next, clamp the bottom panel onto the scrap wood and bench, and drill 1/4" drain holes in each of the four corners.
7. Before putting the box together, cut a couple of 4" square spacer blocks to go inside. Then your sides just butt up to them, and a couple of elastics or clamps will hold everything in place. Clamp the side panels 4" apart using the spacer blocks at the top and bottom. Make the bottom spacer flush with the bottom, then clamp the bottom panel to the bottom spacer block. Drill pilot holes through the bottom panel into the bottoms of the side panels-two per side, trying to avoid any knots in the wood. (Use a 1/8" bit and make these pilot holes 1" deep. You can mark the depth on your bit with a piece of masking tape, and just drill until you get to the tape.) These holes will keep the wood from splitting as the screws go in. Screw the bottom onto the sides, and remove the clamps. Drill pilot holes first, then screw the front and back panels onto the side panels, two screws per side, so they are flush with the sides and bottom.
8. Bevel the roof to fit against the back panel. To find the angle to be planed, place the roof on top of your side panels, offsetting it slightly to one side. Place a ruler beside the roof, with the ruler's edge up tight against the back panel, and mark a line (running parallel to the back panel) on the side of your roof. Repeat on the other side. Connect the lines as in Step 4. Using the line on the longer side as your guide, cut the roof to length. Place the roof in the vise, again make a shallow saw-cut on your line at the far edge, and bevel to suit the angle. (If you don't have a plane to get this bevel at the back panel, you'll need to tack a flap of inner-tube rubber over the joint of the roof and back, so water doesn't lay in the joint and run down into the nest box.) A handsaw or knife could also be used to carefully bevel the roof. For decorative purposes, you could also bevel the lead edge of the roof.
9. On the underside of the roof overhang, 1/2" in and parallel to the lead edge, draw a straight line. Using a handsaw, make a 1?8" deep saw cut all the way across the panel. This prevents rainwater from running up under the roof and down the wall into the nest box. Position the roof so that it overhangs equally on both sides, pre-drill and screw it down. On my nest box I simply used a piece of leftover cedar shingle as the roof, and lightly tacked it down so I can remove it at the end of the nesting season for cleaning purposes. However, you can use more solid stock for durability; remove for cleaning by backing out the screws holding it on.
10. Now that the nest box is watertight, it's time to decorate. I used some leftover cedar shingles to panel the outside of mine, transferring the holes onto them before fastening. Wood glue will hold these, but if you prefer to add a few finish nails, be mindful that they don't protrude into your interior. If you paint the outside of your nest, light colours are best because they reflect rather than absorb heat. Or find an interesting piece of bark or firewood and attach it to the front of the house. Don't add a perch-predators use these, and birds don't need them.
- Tape measure
- CompassHandsaw or alternative
- Block plane
- Electric drill
- 1/8" drill bit
- 1/4" drill bit
- 1 1/2" bit or coping saw
- Selection of clamps, 5 1/2" opening minimum, or rubber bands
- Screwdriver, or driver bit for the drill
- Selection of 3/4" thick boards or 5' of dressed 1"x 6". Rough lumber is great but remember to adjust your dimensions for the increased thickness.
- 1/4" screws, or alternative depending upon the thickness of your lumber. You will need about 16 of them.