Cedar Birdhouse: Why the Drain Holes Matter
Four tiny drain holes in the floor are what keep rain from pooling inside and rotting the nest, so the house lasts for seasons instead of one wet spring.
![[#~image_alt_1~#]](/_next/image?url=https%3A%2F%2Fd3klpa3rfwubzz.cloudfront.net%2Fmedia%2FAPI%20Uploads%2FDIY%2F26d67b07a6375ddde50f6cc3a5a4745f_09938b114e.jpg&w=1920&q=75)
Most homemade birdhouses fail for one boring reason: water gets in through the entrance hole and has nowhere to go. A flat, sealed floor turns into a soggy tray, the wood swells and rots from the inside, and any eggs or chicks get chilled and damp. The fix is four small drain holes drilled through the floor before you assemble anything, plus a slightly angled roof overhang so rain runs away from the entrance. This Woodworking Wednesday build uses one cedar fence picket, a handsaw, a drill, and screws, and it comes together in an afternoon for about $15. Cedar resists rot naturally, so you can leave it unpainted and unsealed, which also keeps chemicals away from the birds.
What You'll Need
- Cedar fence picket, 1x6 by 6 feet, about $6
- Exterior screws, 1-1/4 inch, a small box for about $4
- Handsaw and tape measure, or use tools you already own
- Drill with bits, 1/4 inch for drain holes, 1-1/2 inch spade or hole saw for the entrance, and a small bit for pilot holes
- Sandpaper, 120 grit, about $2
- Pencil and speed square, for marking square cuts
- Galvanized wire or a mounting bracket, for hanging, about $3
How to Build It
- Mark the picket with a pencil and square: front 9 inches, back 11 inches, two sides 8 inches each (cut one end of each at an angle), floor 4 inches, roof 8 inches.
- Cut all pieces with a handsaw, keeping the blade on the waste side of each line. Angle the top of the front and back panels so the roof slopes.
- Drill four 1/4 inch drain holes through the floor piece, one near each corner. Then drill the 1-1/2 inch entrance hole about 2 inches below the top of the front panel.
- Sand the edges and the inside of the entrance hole. Skip the inside walls of the box, because rough wood helps chicks climb out.
- Pre-drill pilot holes, then screw the two side panels to the floor, setting the floor slightly up from the bottom edge so rain can't wick in.
- Attach the front and back panels with screws. Check that the box sits square and the drain holes are clear.
- Fasten the roof with a 1-inch overhang at the front, screwing only one side so you can open it later for yearly cleaning.
- Mount the house 5 to 10 feet up on a post or tree with a bracket or wire, facing away from prevailing wind, and leave the cedar unfinished.
Add a few shallow saw kerfs or scratches on the inside of the front panel below the entrance hole. They act as a tiny ladder so fledglings can climb out when it's time to leave, and nesting birds will thank you for it. Also skip the perch: it only helps predators.
