C&C cages are do-it-yourself enclosures built from two simple materials: wire storage cubes and corrugated plastic. That's where the name comes from—cube and Coroplast®, with Coroplast being a common brand of corrugated plastic. It's the most common cage style used among experienced owners, valued for being inexpensive, easy to build, and fully customizable to fit any space.

Many pet store cages fall short of recommended cage size minimums, with some offering as little as 4–6 square feet of floor space. C&C cages make it easier to provide more room without spending a fortune, and their modular design lets you build around the space you have and change the layout later. You can add an L-shape to fit an awkward corner, build a loft, or expand the cage by adding more grids as your needs change. If you bring home another guinea pig, you can extend the base rather than replacing the entire setup. The corrugated plastic base also wipes clean with ease, while the open wire sides provide excellent ventilation.

Grid Safety

Not all storage grids are safe for guinea pigs, and choosing the wrong size is one of the easiest mistakes to make when planning a C&C cage. Grids are designed for storage, not animal housing, so retailers have no reason to consider guinea pig safety when choosing the wire spacing. Always check the actual grid measurements before buying, rather than assuming any grid is safe.

Storage grids are sold in different overall panel sizes, with 14 inch and 12 inch wide panels both common. The overall width of the panel does not determine whether a grid is safe—the size of each opening does. What matters most is the distance between the wires. Tightly spaced wires create smaller openings, while wider spacing can leave gaps large enough for a guinea pig to get its head through. Always check the opening size rather than relying on the panels overall dimensions.

When comparing grids, look for two important measurements:

Opening width: Each opening should be no wider than 1½ inches. A panel with nine openings across is a useful rule of thumb, but always measure the actual openings because manufacturers can vary. Wider openings create a risk of a guinea pig getting its head stuck, potentially causing serious injury or death.
Grid height: At least 14 inches. Shorter grids are easier to climb over, which becomes especially dangerous on an elevated cage or when intact males and females are housed nearby.

If your grids have openings larger than 1½ inches, replace them with grids that have smaller openings as soon as possible. If replacing them is not immediately practical, overlapping two grids can reduce the opening size and provide a safer temporary solution.

How To Build A C&C Cage

With safe grids in hand, here's what else you'll need and how to put it all together.

What You'll Need

Cubes: Wire storage cubes aren't actually designed for use with animals, so choose storage grids that meet the safety requirements above. You'll need enough grids to create the cage walls and any dividers, lofts, or other features you plan to include.
Corrugated plastic: This forms the waterproof cage tray, and can be found at stores like Home Depot, Lowe's, or local sign shops.
Cable ties: You'll need these to zip-tie the grids together so the cage is stable, secure, and escape-proof. The plastic connectors that come packaged with storage cubes help with shape and stability, but they aren't sturdy enough to rely on alone. Always reinforce every joint with cable ties for safety.
Yard stick and a marker for planning your base and marking fold lines.
A utility knife or box cutter and a metal ruler or straightedge for scoring and cutting the corrugated plastic.
Wire cutters or scissors to trim excess cable tie ends once the cage is assembled (trimmed ends prevent scratches and stop curious pigs from chewing on sharp tips).

Step-by-Step

Plan your layout. Decide on your cage dimensions (for example, 2x4 grids for a pair). Sketch it out so you know exactly how many grids and connectors you'll need. Our C&C Grids Calculator can help you determine how many grids are needed for a particular build.
Cut your corrugated plastic base. Lay your grids out in the shape of your planned cage to get exact dimensions, then cut your Coroplast® sheet to size, adding roughly 6 inches of extra material on each side. This extra material folds up to form a lip around the base, which keeps bedding, hay, and spills contained.
Score and fold the sides. Using your utility knife, lightly score (don't cut all the way through) each fold line on the underside of the corrugated plastic, about 6 inches in from each edge. Fold the sides up along these lines to create a shallow tray. Corrugated plastic bends cleanly along the direction of its internal ribs, so pay attention to which way the corrugation runs when you plan your cuts.
Reinforce the corners. Once folded, secure each corner of the Coroplast® tray with waterproof marine tape (inside and out) so it holds its shape and won't leak.
Assemble the grid frame. Connect your cubes into the perimeter shape you planned, using the plastic connectors for the basic frame. Work on a flat surface so the frame stays square as you go.
Zip-tie every joint. Go around the entire frame and add a cable tie at each connection point, even where a plastic connector is already in place. This is what actually keeps guinea pigs from working a gap open and escaping, so don't skip corners. Trim the excess tail off each tie once it's tightened.
Put it together. Place the folded Coroplast® tray inside the assembled grid frame so the plastic walls sit just inside the wire grid.
Do a safety check. Run your hand along every seam and connection point to check for gaps, sharp cable tie ends, or wobbly joints before your guinea pigs move in. Give the whole structure a gentle shake test—nothing should flex or separate.
Add levels or a lids (optional). If you're adding a loft, use a shallow ramp (guinea pigs don't do well with steep inclines) and keep in mind that lofts don't add to your cage's floor space—guinea pigs are ground-dwellers and rely on floor area, not height. A cover isn't usually necessary for guinea pigs since they don't jump, but one can help keep other pets or young children out.

Ready-Made Kits

If cutting your own Coroplast isn't for you, several retailers offer complete C&C cage kits with pre-scored bases, safe grids, connectors, and cable ties. Kits are a convenient option if you want the flexibility of a C&C cage without measuring and cutting the base yourself:

Low Budget C&C Cages

A C&C cage doesn't have to mean cutting and folding Coroplast®. The design is versatile by design, and flexible enough to build with just the essentials: safe grids, a waterproof base, and cable ties. That makes it not just cheaper, but also a more accessible entry point if cutting and scoring plastic, or sourcing tools like a utility knife and straightedge, feels daunting or isn't an option for you.

If you're on a budget, short on tools, or just want the simplest possible build, here's a stripped-down version:

Skip the Coroplast® base. Instead of cutting and folding a corrugated plastic base, use a shower liner or a waterproof tarp underneath your grid frame. It won't have the folded-up lip of a proper tray, so it works best combined with a fleece cage liner to reduce mess.
Try utility or plant trays. Shallow plastic utility trays, boot trays, or even large plant/garden trays can serve as a ready-made waterproof base—no cutting required. Look for trays wide to fit inside your grid footprint. Trays work best for disposable bedding.
Zip-tie your grids together. The build process is otherwise the same: assemble your grids into the shape you want, and reinforce every single joint with cable ties. Plastic connectors add extra stability but aren't strictly necessary—the cable ties are what actually hold the frame together.

This approach trades a bit of durability and spill containment for cost and simplicity, but it's a perfectly workable cage as long as your grids are safe and every joint is properly zip-tied.

Safety Notes

Watch for chewers. Some guinea pigs like to gnaw on the plastic base. If your guinea pig is a persistent chewer, corner guards or edging made can protect both the cage and your pets.

Don't skip the cable ties. Plastic connectors alone can pop apart under pressure. A guinea pig pushing against a weak seam is often all it takes to escape.

Trim cable ties flush. Cut the excess tail as close to the base of the zip tie as possible. Leftover sharp ends can cut your guinea pig or snag on things during cage cleaning. Human nail clippers work well for getting a clean, close cut.

Inspect cable ties periodically. Ties can loosen or crack over time, especially with a persistent chewer or a very active herd. A quick monthly check-and-retighten catches problems before they become an escape route.

Watch for rust on the grids. If your cage is in a humid spot or near frequent spills, wire grids can eventually rust. Rusted wire is more likely to break or fray, so replace a grid if you see this.