Quick answer: A washable cardboard cave pairs a cheap, replaceable cardboard shell with a removable fleece liner and a fabric slipcover that come off for washing. Build the shell from clean box remnants using only paper tape or non-toxic glue, cut a wide doorway, and replace the cardboard once it is chewed, soiled or soft.
Kittens love boxes, but plain cardboard soaks up spills and accidents and cannot be cleaned. The idea here is to keep cardboard for what it does well, giving shape and a cosy feel, and add washable fabric layers where hygiene matters. When the shell wears out, you rebuild it in minutes and keep the liner and cover.
The design suits young kittens settling into a new home. Our first-week guide explains how a hideaway fits into the wider plan.
Why Kittens Need a Cave
International Cat Care notes that cats value places to disappear from view. For a kitten in a new home, a small covered spot provides security while it learns the sounds and smells around it. Cats Protection advises letting a new cat come out in its own time, and a cave gives it somewhere to do that.
A cave also gives the kitten a sleep spot that is clearly its own. Kittens sleep a great deal, and a warm, enclosed bed near the family helps them rest without being disturbed.
Choosing Cardboard Remnants for a Washable Cardboard Cave
| Remnant | Use it? | Notes |
|---|---|---|
| Plain double-wall shipping boxes | Yes | Strong, holds shape |
| Single-wall boxes | For inner parts only | Bends quickly |
| Glossy printed boxes | Avoid | Inks and coatings may flake |
| Boxes with heavy tape or staples | Strip first | Remove all metal and plastic tape |
| Food or detergent boxes | Avoid | May hold residues and smells |
Our guide to tapes, inks and staples to avoid lists the materials to remove before building. For kittens that also scratch the cave, see the best corrugated cardboard for kitten scratchers.
A cave also helps on vet days and when visitors arrive, because the kitten already has a known retreat to head for instead of squeezing behind appliances.
Building the Shell
- Cut a box to about 40 by 35 by 30 cm for a kitten, larger for adults later.
- Cut a doorway about 15 cm wide, rounded at the top, with the bottom a few centimetres up.
- Reinforce corners with an extra strip of cardboard glued inside.
- Use paper tape or a non-toxic, water-based glue; avoid plastic tape.
- Let glue dry fully and air the shell for a day before use.
Add a small second opening at the back if the cave sits in a shared room, so the kitten never feels trapped. Smooth any rough cut edges by folding a strip of paper over them.
Making the Liner and Slipcover
The washable parts do the hygiene work. A liner covers the floor of the cave and a slipcover wraps the outside, so dirt, fur and spills land on fabric rather than cardboard.
- Liner: two layers of fleece cut slightly bigger than the floor, folded up the sides.
- Slipcover: a fleece or cotton tube that pulls over the shell, with the doorway cut and hemmed.
- No sewing option: cut fleece with pinking shears and tie edges in short knots outside.
- Make two of each so one is always clean.
Keep strings, ribbons and loose threads off the cave. Kittens chew, and long fibres can be swallowed. Trim any loose knots so nothing dangles inside.
Fitting the Cover Neatly
A slipcover that bunches at the doorway gets pulled, chewed and soiled faster. Measure around the shell and add a few centimetres for ease, then try the cover on before cutting the doorway. Mark the opening with chalk from the inside, take the cover off and cut slightly smaller than the cardboard hole so the fabric can fold inward.
Fold the fabric edge inside the doorway and hold it with a few dabs of water-based glue on the cardboard, or with small fabric clips on the inside where the kitten cannot reach them. When it is time to wash, peel the edge away and slide the cover off in one piece.
- Choose fleece in a mid tone that hides fur between washes.
- Avoid fabrics with sequins, buttons or loose decorations.
- Pre-wash new fabric to remove factory finishes and smells.
- Mark the front of the cover so it goes back the same way each time.
Where to Put the Cave
Place the cave in a quiet corner of the room the kitten uses most, away from the litter tray and food. A spot near the sofa or your desk works well, since the kitten can watch the family from safety.
| Good spot | Avoid |
|---|---|
| Corner of the living room | Next to the litter tray |
| Beside your bed | In a busy hallway |
| Near a radiator but not touching | On a high shelf a kitten can fall from |
| On a rug off cold tiles | Under a dining table where chairs move |
Put a scratch pad beside the cave so the kitten has an outlet after naps. Kittens often scratch on waking, and a pad next to the bed protects the sofa.
Using the Cave for Play as Well as Rest
International Cat Care notes that boxes or tunnels can make play more stimulating for kittens and that sessions may last only a few minutes before a kitten tires. Drag a wand toy around the cave entrance and let the kitten pounce out, then let it rest inside.
Keep the cave mostly for rest, though. Our 10-minute play circuit for kittens and zero-waste kitten toys from packaging give play ideas that keep the cave a calm place.
Safety Checks for Young Kittens
Very young kittens explore with their mouths, so check the cave daily during the first weeks. Look for torn cardboard flakes on the floor, loose threads on the liner and any glue that has softened. Remove anything small enough to swallow.
Keep the cave on the floor rather than on furniture until the kitten is confident and coordinated. A fall from a sofa arm onto a hard floor can hurt a small kitten, and a cave on a shelf can tip when it jumps in. Once the kitten is older, a raised spot can be added with a secure base.
| Check | Action if found |
|---|---|
| Chewed cardboard pieces | Trim the edge or rebuild the shell |
| Loose threads or knots | Trim short or replace the fabric |
| Damp liner | Wash and dry fully before refitting |
| Wobbly shell | Reinforce corners or rebuild |
Washing Schedule for the Liner and Shell
| How often | Task |
|---|---|
| Daily | Shake out the liner and check for accidents |
| Weekly | Wash liner and slipcover with unscented detergent |
| After any accident | Wash fabric and replace the cardboard shell |
| Every few weeks | Check the shell for chewing and soft spots |
Fabric washes clean; cardboard does not. If urine or vomit soaks through to the shell, recycle it and build a new one from fresh remnants. It takes less than half an hour once you know the steps.
When to Upgrade
As the kitten grows, it may outgrow the shell or start to chew it apart. At that point, rebuild larger, or move to a sturdier cave in wood or felt and keep the liner as a bed. Our beds and caves hub has longer-lasting designs, and the cardboard castle build shows a bigger play structure for active kittens.
Many owners keep a cardboard cave in use long after the kitten stage simply because cats enjoy fresh boxes. Rebuilding every month or two gives the cat a new scent to explore, and the washable liner and cover carry over, so the familiar smell of its bed stays the same while the shell changes.
Cardboard Kitten Cave Questions
Can a cardboard cave really be washable?
The cardboard shell itself is not washable, but the liner and slipcover are. Fabric takes the dirt and spills, so you wash those weekly and replace the shell only when it gets soiled or chewed. That keeps the cave clean while still using free cardboard remnants.
What tape is safe for a kitten cave?
Use paper tape or a non-toxic, water-based glue, and let it dry fully before use. Avoid plastic packing tape, staples and glossy printed boxes. Kittens chew and lick their dens, so remove all metal, plastic and loose bits from remnants before building.
How big should a kitten cave be?
About 40 by 35 by 30 cm suits most kittens, with a doorway about 15 cm wide. That lets a kitten turn and curl up without feeling exposed. Build a larger shell as the kitten grows, since adult cats need more room to stretch and turn.
How often should I replace the cardboard?
Replace it after any accident that soaks through, or when it becomes soft, torn or heavily chewed. With a liner and cover doing most of the work, a shell often lasts several weeks. Check it during weekly washing and rebuild from fresh remnants when needed.
