Litter box cabinet plans, sized to your space

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 and a straight edge (or have the store cut the sheets)
• Hammer
• Jigsaw
• 1 1/2″ hole saw
• 35 mm Forstner bit (or a hinge-boring jig)
• Household iron
• Utility knife
• 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. Cut sheets with the good face down when using a circular saw: the blade splinters the top face.

   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. 3Cut the cat door

   On the inside face of the left side (A), draw the cat door: 7″ wide and 8″ tall, centred front to back, its bottom 2 11/16″ up from the bottom edge. The 2″ step left above the cabinet floor keeps scattered litter inside.

   Round the top: set a compass to 3 1/2″ and draw a half circle from the centre of the top line.

   Drill a 1/2″ starter hole inside each bottom corner, then saw round the outline with a jigsaw, staying just inside the line.

   Sand the edges round and smooth with 120 grit. A cat brushes through this hole several times a day.

   • Tip Clamp the work so the line hangs off the bench, use a fine-tooth wood blade, let the saw reach full speed before it touches the wood and push gently: the blade bends if you force it, and the cut wanders.

   ✓ The hole is 7″ wide at its widest and every edge is smooth to a fingertip.

   STOP. Clamp the side to the bench and keep your other hand behind the saw.

4. 4Drill the vent holes

   Litter smells and dust need somewhere to go. On the back (D), mark 9 holes in a row 2″ below the top, about 3″ apart. On the plain side (B), mark 3 more, 2″ below the top.

   Drill each with a 1 1/2″ hole saw: clamp the panel over scrap, let the pilot bit centre it, and drill until the teeth just break through. Finish from the other side for clean edges.

   Sand the inside of each hole.

   ✓ 12 clean holes, all near the top where warm, smelly air collects.

   STOP. A hole saw can grab and wrench the drill: hold it with both hands, run it at low speed, and clamp the panel.

5. 5Assemble the case

   Lay out the parts: the cat-door side and the plain side face to face, the top and bottom between them, front edges all one way.

   Glue the ends of the top and bottom (C) and set them between the sides, flush at the front, back, top and bottom. Drive 3 screws, 1 5/8″, through each side into each panel, predrilled and countersunk, centred on the 3/4″ edge.

   Glue the top stiffener (F) on edge under the front of the top, flush with the front edges, and drive 2 screws through each side into its ends plus one down through the top every 8″. It stops a 31″ plywood top sagging under a plant or a stack of books.

   Measure both diagonals of the front opening; push the case until they match.

   • Tip Spread a thin, even layer of glue on one face with a finger or scrap: enough that a little beads out when you clamp, not so much that it runs. Wipe the squeeze-out with a damp rag right away, or scrape it once it turns rubbery; dried glue blocks stain and finish.
   • Tip Measure both diagonals, corner to corner. If they match, the assembly is square. If not, push the long diagonal's corners toward each other until they do, then let the glue set.

   ✓ The front opening measures 31″ × 17″ and its diagonals match within 1/8″.

6. 6Nail on the back

   Lay the case face down. Run a thin bead of glue along the back edges of the sides, top and bottom.

   Lay the back (D) on, vent holes at the top. Line up one long edge and one short edge exactly: a square back pulls the whole case square.

   Drive 1″ brads every 4″ all round, angled very slightly toward the middle of each 3/4″ edge.

   ✓ The back is flush with the case on all four edges and the diagonals of the front still match.

7. 7Sand and finish

   Sand every face and edge of the cabinet and door with 120 grit, then 180 grit, always moving along the grain (the lines in the wood). Sanding across the grain leaves scratches that the finish makes darker.

   Soften every sharp edge and corner with a few strokes of 180-grit paper on a block, so edges don't splinter or chip.

   Vacuum the dust, then wipe with a tack cloth or a barely damp rag and let it dry 10 minutes.

   Use a water-based polyurethane or a water-based paint: they smell less and cure faster than oil-based finishes. Skip anything labelled "exterior only" or for decks.

   Brush on thin coats along the grain, sanding lightly with 220 grit between coats once each is dry. Three coats on surfaces that get wet or scratched.

   Let the finish cure a full 7 days before your pet uses it: pets lick, chew and sleep on it, and finish that is dry to the touch is not yet cured.

   • Tip Pine goes blotchy under stain. If you want colour, brush on a pre-stain conditioner first, or use a gel stain.
   • Tip Finish the back and underside too. Wood that is sealed on one side only can cup as the seasons change.
   • Tip Work in a warm, dry, well-ventilated room. Below about 50°F (10°C) most finishes dry slowly and cloudy.

   ✓ The surface feels smooth and even, with no drips on the edges and no dull, dry patches.

8. 8Hang the door

   Iron edge banding onto the four edges of the door (E): cut a strip 1″ longer than the edge, hold it on with the glue side down, and run a household iron (cotton setting, no steam) slowly along it. Press it down with a block of wood while it cools, then trim the overhang with a utility knife held flat and sand the edges lightly.

   The door hangs on 2 full-overlay cabinet hinges on the right side. On the back of the door, mark hinge centres 3″ from the top and bottom, 7/8″ in from the hinge edge. Drill a 35 mm cup hole at each, 1/2″ deep, with a Forstner bit in a drill press or a hinge-boring jig.

   Press the hinge cups in and screw them down. Hold the door on the cabinet with 1/16″ gaps all round (stack two coins as spacers), mark where the mounting plates meet the side, and screw the plates on.

   Clip the door on and use the hinge adjustment screws to even the gaps. Add the pull and the magnetic catch.

   • Tip Drill a test cup hole in scrap first: too deep and the point breaks through the face of the door.

   ✓ The door closes flat against the case with even gaps all round and the catch holds it shut.

9. 9Set up the litter box

   Slide the litter box in at the far end from the cat door, so the cat steps through the 8″ entry area first and litter falls off its paws before it leaves.

   Put a litter mat outside the cat door, and felt pads under the cabinet.

   Leave the front door open for the first few days so your cat can see in and get used to it.

   ✓ Your cat goes in and out by itself, and the box slides out easily through the front door for cleaning.