Tree swallow birdhouse plans

Parts

Cut list

Kerf 1/8″ included. Every cut runs edge to edge.

Steps

• Tape measure
• Speed square
• Pencil
• Drill/driver
• Clamps
• Safety glasses
• Hearing protection
• Dust mask
• Circular saw or miter saw
• Miter saw, or circular saw in two passes, for 4×4 posts
• Table saw or track saw for ripping
• Spade bit or hole saw, 1 1/2″
• Handsaw
• Sander, 120 and 180 grit

Underlined words have a short explanation: hover or tap them. All of them are on the glossary page.

1. 1Before you start

   Read every step once, start to finish, before you buy or cut anything. Each step names the parts it uses by letter; the parts list gives their sizes.

   Set up somewhere flat with good light. A pair of sawhorses with a sheet of plywood on top makes a fine work table.

   Wear safety glasses whenever a tool is running, hearing protection for saws, and a dust mask for sanding and for cutting treated wood or sheet goods. Tie back long hair and loose sleeves. Keep children and pets out of the work area.

   • Tip At the store, pick straight boards: hold each one up to your eye and look down its length. Skip boards that bow, twist or have big knots near the ends.
   • Tip Measure twice, cut once. Most mistakes are a misread tape, not a bad cut.

2. 2Cut and label the parts

   Cut every part on the cut list. Cut the longest parts first: if one goes wrong, it can still become a shorter part.

   To mark a cut, hook your tape on the end of the board, make a small V with its point exactly at the measurement, and draw a square line through the point with a speed square. Put an X on the waste side.

   Cut on the waste side of the line, so the blade's kerf (about 1/8″) comes out of the scrap, not your part.

   Write each part's letter in pencil on a face that won't show, and stack the parts by letter.

   Sand the faces before assembly while they're flat and easy to reach: 120 grit, then 180.

   ✓ Lay the parts out and count them against the parts list. Measure a few: if one is off by more than 1/16″, recut it now.

   STOP. Let the saw reach full speed before it touches the wood, keep both hands clear of the blade's path, and never reach under a board you're cutting. Support long boards on both sides of the cut so the blade doesn't pinch.

3. 3Pick the boards and the screws

   Cedar for the birdhouse: look for boards with mostly reddish-brown heartwood. Pale yellow-white streaks are sapwood, which rots years sooner; keep those streaks on the inside or skip the board.

   Pressure-treated pine: read the end tag. Parts that touch soil, sit in wet mulch or go in the ground must say "ground contact"; "above ground" lumber is fine for everything else. New treated boards are often wet and heavy: stack them flat with scrap sticks between them for a week or two in the shade so they dry and stop twisting.

   Sight down each board at the store like a rifle barrel. Skip boards that twist, bow more than about 1/4″ over 8′, or have big loose knots near where you will cut or screw.

   Use exterior screws only: coated deck screws (labelled for treated lumber, "ACQ compatible") or stainless steel. The copper in treated wood eats plain and zinc-plated steel within a few years. Indoor wood screws and drywall screws rust and snap outdoors.

   Animals chew and lick wood. Keep pressure-treated lumber to the legs and frame outside the living space, and use cedar or exterior plywood for anything they touch inside.

   • Tip Buy one extra board of the most-used size. A split or a mis-cut then costs you nothing but a few dollars.
   • Tip Cedar splits easily: predrill every screw within 2″ of the end of a board with a bit about the size of the screw's inner shank.

   ✓ Every board is reasonably straight, and the screw box says exterior, coated for treated lumber, or stainless.

4. 4Shape the sides and the floor

   Mark each side (C, D) 11 1/4″ tall on the back edge and 9 1/2″ on the front edge, and join the marks with a straight line. Cut along it: the roof slopes down to the front so rain runs off away from the hole.

   The sides are 1/4″ shorter than the roof line on purpose. That slot under the roof is the ventilation: hot air escapes there and the chicks don't cook in summer.

   Clip 3/8″ off each corner of the floor (E) with one saw cut across the corner. Those little gaps are the drainage holes: rain that blows in runs straight out.

   • Tip Clamp a small part to the bench and cut it with a handsaw rather than holding it near a power saw blade.

   ✓ Hold the two sides together: the sloped tops match exactly, and the door side is 1/8″ narrower than the other.

5. 5Drill the entrance hole

   Mark a centre line down the front (B). Mark the hole centre 7 1/4″ up from the bottom edge: the bottom of the hole ends 5 1/2″ above the floor, so chicks can't fall out and cats can't reach in.

   Clamp the front onto a scrap board and drill the 1 1/2″ hole with a spade bit or hole saw. Drill until the tip pokes through, then finish from the other side so the edge doesn't splinter.

   On the inside face, below the hole, saw 4 or 5 shallow grooves across the grain about 1/2″ apart and 1/16″ deep. They are a ladder for the fledglings to climb out.

   Do not add a perch under the hole.

   • Tip Sand the hole edge lightly so it doesn't catch feathers.

   ✓ The hole measures 1 1/2″ across, not more: a bigger hole lets in starlings and house sparrows, which kill the birds you want.

6. 6Join the back, the fixed side and the floor

   Lay the back (A) flat, inside face up. Draw a line across it 3″ up from the bottom: that is where the bottom of the walls sits. The extra 3″ below and above is for the mounting screws.

   Stand the fixed side (C) on the back along one edge, its bottom on the line and its tall end against the back. Predrill and drive two 1 5/8″ screws through the back into it.

   Set the floor (E) against the side, 1/4″ up from the line, and screw through the back and through the side into it: two screws each.

   ✓ The side is square to the back (check with a speed square) and the floor sits 1/4″ above the bottom edge of the side.

7. 7Add the front and the swinging door side

   Screw the front (B) onto the front edges of the fixed side and the floor, bottoms flush with the side. Two 1 5/8″ screws into the side, two into the floor.

   Slip the door side (D) into the open side, bottom flush. Drive one screw through the front and one through the back into its edges, both exactly 1″ below its top and directly across from each other: those two screws are the hinge.

   Check it swings out at the bottom. Then screw the hook-and-eye at the bottom front corner to latch it shut.

   • Tip Predrill the pivot holes in the front and back a little larger than the screw so the door turns easily.

   ✓ The door side swings out freely and latches flush; both sides show a 1/4″ slot under the roof line.

   STOP. Don't screw the floor or the roof into the door side, or it won't open for cleaning.

8. 8Put on the roof

   Set the roof (F) on the front and the fixed side, its back edge tight against the back board, overhanging 2 1/2″ at the front and the same amount each side.

   Drive two 1 5/8″ screws down through the roof into the top of the front, and two more through the back board into the roof's back edge.

   The 2 1/2″ front overhang shades the hole and keeps rain and cat paws out.

   ✓ The door side still swings, and rain poured on the roof runs off the front, clear of the hole.

9. 9Protect it from the weather

   Decide how you want the birdhouse to look in five years. Bare cedar and bare pressure-treated wood both weather to silver-grey and still last many years; doing nothing is a real option.

   To keep the colour, use an exterior oil or semi-transparent stain: brush it on, let it soak in 15 minutes, then wipe off whatever is still shiny. Renew it every one or two years. Avoid clear varnish or polyurethane outdoors: sun cracks the film, water gets under it, and it peels.

   For a solid colour, prime with an exterior primer and use two coats of exterior latex paint. Paint end grain twice: it soaks up water like a straw.

   Finish only the outside. Leave inside faces bare, and let any finish dry and air out for at least a week before an animal moves in: fresh fumes are hard on small lungs.

   • Tip Finish on a dry day above 50°F with no rain forecast for 24 hours.
   • Tip Oil-soaked rags can catch fire on their own as they dry. Lay them flat outside to dry or keep them in a sealed metal can of water.

   ✓ The finish is dry to the touch everywhere, with no wet or shiny puddles in corners.

10. 10Dig the post holes

    Dig a hole 10″ wide and 31″ deep with a post-hole digger.

    That depth is 25″ for the post plus 6″ of gravel underneath so water drains away from the post end.

    Make the holes slightly wider at the bottom than the top, like a bell. Frost then can't grip the concrete and lift it.

    Pour 6″ of gravel in each hole and tamp it with the end of a 2×4 or the post itself.

    • Tip Your town knows the frost depth: it's how deep footings must go so winter frost can't push them up. Enter it in the options and the holes will be dug deep enough.

    ✓ Every hole is 31″ deep before the gravel and 25″ deep after it.

11. 11Set the posts plumb

    Stand a post in each hole. Run a string between the end posts at the height you want, to line up the ones in between.

    Hold a level against one face of a post until the bubble is centred: that face is plumb. Then check the face around the corner. Both faces must read plumb.

    Brace each post with two 1×4 or 2×4 boards: screw one end to the post and the other to a stake hammered into the ground, one brace on each of two sides at right angles.

    ✓ Every post is plumb on two faces, in line with the string, and the braces hold it there when you let go.

12. 12Mix the concrete

    You'll use 2 bags of 80 lb concrete mix for the post hole. Mix one or two bags at a time in a wheelbarrow: concrete starts to stiffen in about 30–45 minutes (faster on a hot day), so only mix what you can place right away.

    Pour about 2 quarts of clean water into the wheelbarrow first, then empty one bag on top. (Each 80 lb bag needs about 3 quarts in total.)

    Mix with a hoe or square shovel: pull the dry powder from the corners and bottom into the wet middle and chop through it. Keep going until there are no dry pockets.

    Add the last of the water a cup at a time, mixing between each.

    Get the thickness right. It should look and feel like thick oatmeal or stiff peanut butter. A hoe dragged through leaves ridges that stand up, and a handful squeezed in a gloved hand holds its shape. Too dry: it crumbles and won't stick together, so add a little water. Too wet: it flows flat, water pools on top, and the concrete will be weak and crack. Then add some dry mix from a spare bag.

    • Tip More water makes concrete easier to push around and much weaker. Resist the urge.
    • Tip Rinse the wheelbarrow, hoe and shovel before the concrete sets on them. Don't wash concrete into drains or onto the lawn: let leftovers harden in a scrap box and throw them out.
    • Tip Buy one more bag than you need. Running out halfway through a pour is the most common mistake.

    ✓ Even grey colour throughout, no dry powder, no puddles of water on top; a ridge made with the hoe stands up.

    STOP. Wet concrete is caustic and burns skin. Wear waterproof gloves, safety glasses, long sleeves and long pants. Open bags slowly and wear a dust mask: the dust has silica. Rinse any concrete off your skin right away.

13. 13Fill the holes

    Shovel concrete into each hole around the post. Every 6″ or so, poke it hard with a stick or a piece of rebar to work out air pockets.

    Fill to about 1″ above the ground and shape the top into a little mound with a trowel, sloping away from the post so rain runs off.

    Check plumb again on both faces while it's still wet, and adjust the braces if needed.

    ✓ Posts are still plumb and in line after the concrete is in.

14. 14Let the concrete cure

    Concrete hardens by reacting with water, not by drying out, so keep the concrete around the birdhouse posts damp for the first 7 days: mist it with a hose morning and evening, or cover it with plastic sheeting held down at the edges.

    Keep it from freezing for the first week. Don't pour when it's below 40°F (5°C) or frost is forecast in the next two days. On hot days, pour in the early morning and shade it.

    You can walk on it or remove braces after 1–2 days. Wait 3 days before putting real weight on it. It reaches full strength in about 4 weeks.

    ✓ The surface is hard and grey-white when dry, with no powder when you rub it.

15. 15Mount it and keep it clean

    Once the concrete has cured, hold the house against the post with the floor 60″ up. Drive two 3″ screws through the back board into the post above the roof and two below the floor.

    Fit the baffle around the post below the house, its top at least 4 ft off the ground, following its instructions.

    Face the hole away from the prevailing wind, ideally east, with open flying room in front of it.

    Put it up by late winter. After each family fledges, open the door side, scoop out the old nest and close it. Never open it while there are eggs or chicks in it except for a quick look.

    • Tip If you paint, use a light colour on the outside only. Dark boxes get hot in the sun; never paint the inside or the hole.

    ✓ The house is plumb, the hole faces open space, and the floor is 60″ up.

16. 16Finish

    Ease every sharp edge and corner with 120-grit sandpaper so nobody gets a splinter.

    Sand all over with 180 grit, always along the grain (the direction the wood fibres run). Scratches across the grain show through stain.

    Wipe off the dust with a barely damp rag and let it dry.

    Outdoors, use an exterior finish: a penetrating deck oil or exterior stain, or primer and exterior paint. Leave cedar bare to weather silver if you like. If it holds soil for food plants, leave the inside unfinished.

    Let it dry for the time on the can before using it.

    • Tip Try your finish on a scrap of the same wood first: stain looks different on every board.