D.I.Y. Playpen

Whether you’re looking to give your rats more floor time or simply want a portable, cost-effective playpen, this easy DIY project is perfect. In just a few simple steps—and using materials you can grab at Dollar Tree—you’ll have a foldable, sturdy playpen that keeps your mischief safe while they explore.

Materials You’ll Need

  1. Poster boards (15 sheets) – We used 22" × 28" black foam poster boards. They’re lightweight, durable, and easy to tape together.

  2. Black duct tape (4 rolls) – You’ll need enough to tape all edges securely.

  3. A spacer tool (optional) – This can be anything from a folded piece of cardboard to the thickness of your fingertip (see Step 2).

  4. Scissors or a utility knife – To trim any rough edges or tape tails.

  5. Measuring tape or ruler (optional) – For extra precision when spacing boards evenly.

Tip: If you want a pop of color, you can grab patterned duct tape instead. Just be mindful that bright colors may show wear more easily, so black often looks neater. You may need to reevaluate how many rolls needed based on the style you go with.

Step 1: Lay Out and Space Your Boards

  1. Lay your first poster board flat on a clean, flat surface (tabletop or countertop).

  2. Place a second board next to it, leaving a small gap roughly equal to the width of your fingertip (about ½ inch). This gap will eventually become the “fold” between boards.

  3. Slide your fingertip (or a temporary spacer block) between the boards to keep the spacing consistent.

  4. Continue laying boards side-by-side, each with that same ½ inch gap, until all 15 boards are lined up, like this:

Why the gap? When you tape the edges, that small space gives you enough slack to fold the boards in an accordion (zig-zag) pattern without putting tension on the tape or cracking the poster board.

Step 2: Create Consistent Spacers

  1. To make sure every gap is exactly the same height, create a pair of “top and bottom” spacers. We used two short strips of poster board folded to about ½ inch thickness.

  2. Slide one spacer under the top edge of each gap and another under the bottom edge, like rails, to keep boards perfectly aligned.

  3. Adjust as you go until the row of boards sits perfectly flush, with equal spacing between every board.

Pro tip: If you don’t have extra poster board, a piece of scrap cardboard or even a couple straws can work as a temporary spacer. The goal is simply to avoid crooked folds later on.

Step 3: Tape Both Sides—Accordion Style

  1. Starting at one end of your row, take a strip of black duct tape about 3–4 inches longer than the height of the poster board.

  2. With the spacer still in place, lay the tape across the front faces of two adjacent boards, bridging that ½ inch gap. Press the tape down firmly so it adheres evenly to both boards.

  3. Then, flip the entire assembly over and place a second strip of tape across the back faces of the same joint (mirroring the first strip). This double-sided reinforcement ensures the joint won’t peel if your rats push against it.

  4. Remove the spacers one joint at a time and immediately fold the boards into a zig-zag (accordion) pattern at that taped seam. You should now have a “mountain” fold or “valley” fold, depending on which way you press.

  5. Repeat this process for each pair of boards, working from left to right (or right to left). When you’re done, all 15 boards will be taped together in a continuous accordion fold.

Step 4: Secure All 15 Boards

  1. By the time you’ve taped all 14 seams (between 15 boards), you’ll use roughly four rolls of black duct tape. On average, each roll provides about 30–35 feet of tape.

  2. Keep an eye on your tape stock—if you’re running low halfway through, stop and grab an extra roll so you don’t run out mid-project.

  3. Once all seams are double-taped, test the accordion fold by “breathing” it in and out. Each panel should collapse and expand smoothly without resistance.

How long will this take? Taping 15 boards with double-layer reinforcement can take about 30–45 minutes, depending on how precise you are with spacing and folding.

Step 5: Final Stack & Storage

  1. Once every joint is taped and folded, compress the entire accordion and stand it on its side. Your final stack will look like a pleated book spine—neat, compact, and easy to store.

  2. Store the playpen folded until playtime. When you’re ready to set it up, simply expand it like an accordion, stand the panels up in a circle (or U-shape), and you’ve instantly created a safe, enclosed space for your rats.

Tip: If you want to secure the ends of the playpen to form a complete circle, use binder clips to hinge the first and last panel together. That way, your playpen is fully enclosed and escape-proof.

Using Extra Boards to Make DIY Rat Toys

Once you’ve built your playpen, you might have a few extra poster boards and scraps of duct tape left over. Instead of tossing them, consider turning them into enriching playground elements:

  1. Hideaway Hutches – Cut a poster board in half and fold it into a simple triangular tunnel. Slide in some shredded paper or fleece scraps for added comfort, and voila—a pocket-sized hideout for your adventurers.

  2. Climbing Ramps – Cut a board into a ramp shape, then lean it against one of the playpen panels. Cover it with a strip of fabric or nonslip mesh so your rats can climb up and survey their territory.

  3. Foraging Boards – Spread a thin layer of fleece or paper on top of a flat piece of poster board. Hide small treats or kibble beneath it so your rats can dig and sniff them out. This mimics natural foraging behavior.

  4. Tactile Shredding Zone – Glue or tape loops of paper and strips of cardboard onto a piece of board. Your rats will love shredding and exploring the different textures.

For additional inspiration (and a full list of Dollar Tree–approved rat-friendly supplies), check out our dedicated Dollar Tree Shopping Recommendations page. You’ll find links to inexpensive, safe materials that work wonders for DIY toys and habitat enhancements.

Final Thoughts

This DIY poster-board playpen is:

  • Inexpensive: All materials can be purchased at Dollar Tree for under $20 total.

  • Portable: The accordion fold lets you set it up anywhere—kitchen floor, living room, or even outdoors under supervision.

  • Customizable: Paint, decorate, or label each panel to match your décor (just use non-toxic, low-odor acrylic paint).

  • Easy to Store: Folds down to a ½-inch-wide stack, tucking neatly in a closet or under a couch.

Give your rats a safe, fun space to explore outside their cage—no heavy wood or permanent walls required. Let us know how your DIY playpen turns out, and feel free to share photos of your clever board-toy creations. Happy building (and happy chewing)!