A DIY enclosure hides the box and contains litter spray for less than $100
A homemade litter box enclosure costs between $30 and $100 in materials and takes a weekend to build. The simplest versions use a plastic storage bin with a hole cut in one side; more finished designs use plywood, paint, and a hinged top for straightforward cleaning. A DIY enclosure works because it gives your cat privacy, reduces litter scatter on your floors, and takes up less visual space than an open box — all without the markup of a commercial unit.
The trade-off is time and basic carpentry skill. You will need a drill, a saw, sandpaper, and the ability to measure twice. If you have used a power tool before, you can build one. If you have not, a storage-bin version requires only a utility knife and takes 20 minutes.
Key Takeaways
- A plastic storage bin enclosure costs $20 to $40 and requires only a utility knife to cut an entrance hole; no tools or assembly needed.
- A plywood box enclosure costs $60 to $100, requires basic power tools, and produces a finished piece that matches your home decor.
- Ventilation and odor control matter more than size — a box that is too small will trap ammonia smell, so measure your litter box first and add 6 inches on all sides.
- A hinged or removable top makes cleaning easier than a fixed roof, and a lip or tray inside catches litter that cats kick out.
- Paint, stain, and weatherproofing are optional but extend the life of plywood and make the enclosure easier to wipe clean.
The storage bin method: fastest and cheapest
Buy a plastic storage bin large enough to hold your litter box with 3 to 4 inches of clearance on all sides. A 40-quart bin works for most standard boxes; a 50-quart or larger works for jumbo boxes. The bin should be opaque or semi-opaque so your cat feels hidden.
Mark an entrance hole on one of the long sides, about 4 inches up from the bottom. The hole should be 6 to 8 inches wide and 7 to 8 inches tall — large enough for your cat to enter without scraping their back. Use a utility knife or a rotary tool to cut the hole. Sand the edges smooth so they do not cut your cat's fur. Drill two small holes near the top of the bin on opposite sides for ventilation, or leave the lid off entirely if odor is not a problem in your space.
Slide the litter box inside. If the bin has a lid, you can cut a hole in the lid for additional ventilation or leave it off. This method works when ready and costs $20 to $40. The downside is that plastic shows wear, stains, and odor over time — most people replace the bin every 18 to 24 months.
The plywood box: a finished look that lasts
A plywood enclosure is a four-sided box with a hinged or removable top. Measure your litter box length, width, and height. Add 6 inches to the length and width, and 8 inches to the height. These dimensions give your cat room to move and allow odor to rise out of the top. For a standard 18-by-24-inch litter box, you would build a box roughly 24 by 30 inches on the base and 24 inches tall.
Buy one sheet of 3/4-inch plywood (usually $40 to $60), a 2-by-4 for the frame ($8 to $12), wood screws, wood glue, sandpaper, and paint or stain. Cut the plywood into two side panels, a back panel, and a bottom. The front is left open or partially open so your cat can enter. Cut an entrance hole in the bottom front corner, 6 to 8 inches wide and 7 to 8 inches tall, the same size as the storage bin method. Sand all edges and surfaces smooth.
Assemble the box using wood screws and glue. Drill pilot holes before driving screws to prevent splitting. Attach a hinged top using two or three hinges so you can lift it to scoop litter and refill. Paint or stain the exterior. A water-based polyurethane finish protects the wood and makes the box easier to wipe clean if litter or urine splashes the outside. This method costs $60 to $100 and produces a piece that looks intentional in your home.
Ventilation and odor control
The biggest mistake in DIY enclosures is building them too tight. A sealed box traps ammonia and creates a smell worse than an open litter box. Ventilation solves this: drill holes in the top corners, leave the top partially open, or skip the top entirely and rely on the open entrance.
If odor is still a problem after ventilation, the issue is usually litter depth or scooping frequency, not the enclosure. A 4-inch layer of litter absorbs more urine than a 2-inch layer. Scooping twice a day instead of once also makes a measurable difference. Some people add a small battery-powered fan inside the enclosure pointing upward to push odor out the top; this works but is not necessary if you have adequate ventilation holes.
Litter scatter — the litter your cat kicks out while digging — is easier to contain. Add a 2-inch lip or tray inside the bottom of the enclosure to catch kicked litter. A piece of vinyl flooring or a rubber mat under the entrance hole also catches litter before it spreads across your floor.
Entrance hole placement and size
The entrance hole should be on the front or side of the enclosure, not the back. Your cat needs a clear sightline to the outside so they do not feel trapped. A hole that is too small forces your cat to squeeze, which can cause stress and accidents outside the box. A hole that is too large defeats the purpose of the enclosure by letting litter scatter out.
The standard size is 6 to 8 inches wide and 7 to 8 inches tall. If your cat is very large or very small, adjust the hole to fit them comfortably. You can test the size by watching your cat enter and exit — they should move through without hesitation or scraping. If your cat is elderly or has mobility issues, a lower entrance (3 to 4 inches from the bottom) is easier to use than a higher one.
Materials and tools you will need
| Method | Materials | Tools | Cost | Time |
|---|---|---|---|---|
| Storage bin | Plastic storage bin (40–50 quart) | Utility knife or rotary tool | $20–$40 | 20 minutes |
| Plywood box | 3/4" plywood sheet, 2x4 lumber, wood screws, glue, sandpaper, paint or stain | Circular saw or hand saw, drill, screwdriver, measuring tape, pencil | $60–$100 | 6–8 hours over one weekend |
Maintenance and longevity
A storage bin enclosure lasts 18 to 24 months before plastic becomes brittle, discolored, or develops odor that does not wash out. You can extend its life by wiping it down weekly with a damp cloth and replacing it if cracks develop or if your cat urinates on the outside.
A plywood enclosure lasts 5 to 10 years if painted or stained and kept in a dry space. Moisture is the enemy — if the enclosure sits in a damp basement or bathroom, the wood will swell and the finish will peel. Wipe up spills when ready and reapply polyurethane every two to three years. If the wood becomes soft or smells like mold, it is time to replace it.
Both types benefit from a washable mat or tray underneath to catch litter and urine. Replace the mat every 6 to 12 months or when it becomes stained or smelly.
Frequently Asked Questions
Can I use a cardboard box instead of plywood?
Cardboard works as a temporary enclosure but breaks down within weeks once exposed to litter dust and urine. If you want to test whether an enclosure works for your cat before building something permanent, cardboard is fine. For anything longer than a month, plywood or plastic is more practical.
What if my cat refuses to use the enclosure?
Some cats feel trapped by an enclosed box. Start with the entrance hole as large as possible and gradually make it smaller over weeks. Leave the top off for the first week so your cat does not feel confined. If your cat still avoids it after two weeks, they may prefer an open box — not all cats like enclosures, and forcing one can cause litter box avoidance.
Do I need to ventilate the top if I leave it open?
No. An open-top enclosure does not trap odor and does not need ventilation holes. The trade-off is that litter scatter is less contained and the enclosure looks less finished. Many people use an open-top design in laundry rooms or basements where appearance matters less.
Can I add a door instead of leaving the entrance open?
A hinged or sliding door is possible but adds complexity and cost. Doors also require your cat to push them open, which some cats dislike. A straightforward entrance hole works better for most cats and is easier to build and maintain.
How do I keep the enclosure from smelling like urine?
Odor comes from urine soaking into wood or plastic over time. Seal plywood with polyurethane before your cat uses it. Wipe up urine spills on the outside when ready. If the inside smells, sprinkle baking soda on the bottom or use a litter additive designed to neutralize ammonia. If the smell persists after cleaning, the wood has absorbed urine and will need to be replaced.