Why C&C Cages Are the Gold Standard
Walk into any pet store and look at their guinea pig cages. Now picture doubling or tripling that space. That is what a C&C cage gives you — proper room for your guinea pigs to actually live, not just exist. C&C stands for cubes and coroplast, and these cages have become the most popular housing option in the guinea pig community for one simple reason: they give your pigs the space they need at a price that does not destroy your wallet.
I built my first C&C cage on a Saturday afternoon with materials from a home goods store and a sign shop. Total cost was about 35 dollars, and the whole build took maybe an hour. That cage was bigger than anything I could have bought for under 200 dollars at a pet store, and it looked better too. Three years later, I have upgraded and expanded it twice, which is another huge advantage — C&C cages grow with you.
If you have been thinking about building one, this guide will take you through the entire process from buying materials to the finished product. No special skills required. If you can use cable ties and a box cutter, you can build a C&C cage.
Materials You Will Need
Let me break down exactly what to buy and where to find it.
Wire storage grids are the structural component. You want the grids with nine-by-nine holes that measure approximately 14 inches square. These are commonly sold in sets of six to eight panels as storage cube organizers at stores like Target, Walmart, Bed Bath and Beyond, and Amazon. A set of eight grids typically costs 15 to 25 dollars. For a standard 2x4 cage, you will need about 16 grids. For a 2x5, plan for 18 to 20.
Critical warning: make sure the grid spacing is no more than 1.5 inches between bars. Some storage grids have wider spacing that a guinea pig — especially a young one — can squeeze through or get their head stuck in. The standard nine-by-nine hole grids are safe. If in doubt, bring a ruler to the store.
Coroplast is the base material. It is corrugated plastic sheeting — the same stuff political yard signs are made from. You can buy it from sign shops, art supply stores, or online. A standard 4x8 foot sheet costs about 10 to 20 dollars and is enough for a 2x4 cage with sides. Some home improvement stores carry it in the plastics section.
Cable ties or grid connectors hold everything together. Cable ties are cheaper and work perfectly well. You will need 40 to 60 of them depending on cage size. Dedicated grid connectors that snap onto the grids are available from C&C cage specialty shops and provide a cleaner look, but they are not necessary.
A box cutter or utility knife for cutting and scoring the coroplast. A ruler or straight edge for measuring. A marker for marking cut lines. That is the full list.
Choosing Your Cage Size
Size is measured in grids. A 2x3 cage means two grids wide and three grids long, giving you about 7.5 square feet of floor space. Here are the standard sizes and what they accommodate.
A 2x3 is the absolute minimum for one guinea pig, though honestly, I would not go this small unless space truly does not allow anything bigger. A 2x4 provides roughly 10.5 square feet and is the recommended minimum for two guinea pigs. This is the most popular size and a great starting point for most owners.
A 2x5 gives you about 13 square feet and is what I consider the sweet spot for a pair. Your pigs will have room to sprint, establish separate hangout spots, and still have space for a dedicated kitchen area. A 2x6 at roughly 16 square feet is luxury living and ideal for three guinea pigs or for owners who want their pair to have maximum space.
My recommendation: build one size larger than you think you need. You will not regret having extra space, and your guinea pigs will use every inch of it. The cost difference between a 2x4 and a 2x5 is one extra sheet of grids and a bit more coroplast — maybe five to ten dollars more.
Building the Coroplast Base
The coroplast base is essentially a shallow tray that holds the bedding and contains messes. Here is how to make it.
First, measure your desired cage footprint. For a 2x4 cage, the interior floor will be approximately 28 by 56 inches (two grids by four grids). Add six inches on each side for the walls — so your total coroplast piece should be about 40 by 68 inches. That gives you roughly six-inch walls on all sides when folded up.
Lay the coroplast flat and mark the fold lines. You will score (not cut through) lines six inches from each edge on all four sides. Scoring means cutting partway through the top layer of the coroplast so it folds cleanly — use a ruler and box cutter with light pressure. Practice on a scrap piece first if you have never worked with coroplast before.
At each corner, you will need to cut and fold to create the box shape. Cut along one score line from the edge to the corner intersection point. Then fold up all four walls and secure the corners. You can use waterproof tape, hot glue, or even cable ties through small holes to hold the corners together. I prefer packing tape on the outside for a clean look, reinforced with hot glue on the inside for durability.
The finished base should look like a shallow rectangular tray with six-inch walls on all sides. Test it by placing it where the cage will go and checking that it sits flat. If it rocks, the scoring might be uneven — a small piece of cardboard under the low spot fixes this easily.
Assembling the Grid Walls
With the base ready, it is time to build the walls. This is the straightforward part.
Stand the grids up around the perimeter of the coroplast base. For a 2x4 cage, you need four grids along each long side and two grids along each short side — that is 12 wall grids total. The grids should stand on the outside of the coroplast base, not inside it. This prevents the bedding from pushing against the grids and creating gaps.
Connect adjacent grids to each other using cable ties or connectors at the top, middle, and bottom of each junction. Use at least two cable ties per junction — three is better for structural stability. The grid walls should feel solid and not wobble when you push on them.
At the corners, overlap the grids slightly and secure them together. Some people place one short-side grid in front of the long-side grid at each corner; others butt them together and tie through both. Either approach works as long as the joint is tight.
Trim the excess cable tie tails with scissors. Loose cable tie ends can poke curious guinea pig noses, so cut them flush.
Adding a Lid (If You Need One)
Guinea pigs are not climbers or jumpers, so a lid is not always necessary. However, you will want one if you have cats, dogs, or young children who might reach into the cage unsupervised. A lid also prevents the occasional ambitious guinea pig from attempting a jailbreak — rare, but it happens.
The simplest lid is made from additional grids laid across the top and secured with cable ties. You can hinge one section with cable ties on one side so it opens and closes like a door for easy access. Some owners use zip ties on one edge as hinges and binder clips on the opposite edge as latches.
If a full grid lid feels too enclosed, you can use garden fencing or lightweight wire mesh cut to size. Just make sure the openings are small enough that a cat paw cannot reach through.
Layout and Interior Design
Now for the fun part — setting up the inside. A well-organized cage layout makes daily care easier and keeps your guinea pigs happy.
Create a kitchen area at one end of the cage. This is where you place the hay rack, pellet bowl, and water bottle. Use a different bedding material in this section if you want — many owners put paper bedding or a puppy pad in the kitchen area since it gets the dirtiest. This keeps the main living area cleaner and extends the life of fleece liners if you use them.
Place hideouts throughout the cage — at least one per guinea pig plus one extra. Wooden houses, fleece forests, tunnels, and even overturned cardboard boxes provide the security that prey animals need. Position them away from the kitchen area so food debris does not accumulate inside them.
Leave open running lanes. Guinea pigs love to sprint from one end of the cage to the other, and cluttering the space with too many accessories defeats the purpose of having a large cage. Think of it like furniture arrangement in an apartment — you need open pathways for movement.
If you want to get creative, you can add a second level by creating a raised platform from a grid supported by cable-tied legs. A small loft with a gentle ramp (lined with fleece for traction) adds vertical space without taking away from the main floor area. Just make sure the ramp is not too steep and has side walls to prevent falls.
Common Mistakes to Avoid
A few pitfalls that are easy to sidestep if you know about them.
Using grids with wide bar spacing is the most dangerous mistake. If a guinea pig can fit its head through the gaps, it can get stuck and potentially injure itself. Test with a measuring tape before buying — bar spacing should be 1.5 inches or less.
Making the coroplast walls too short leads to bedding being kicked out constantly. Six inches is the minimum wall height. If your guinea pigs are particularly messy, you can go up to eight or ten inches.
Not securing the grids to the coroplast base can result in the walls shifting and creating gaps. Use cable ties through small holes in the coroplast to anchor the bottom grids to the base. It takes five extra minutes and prevents escapes.
Placing the cage directly on carpet is a recipe for moisture damage. Put a waterproof layer — a plastic sheet, a tarp, or even a vinyl tablecloth — under the entire cage if it is on carpet. Accidents happen, and coroplast joints are not perfectly watertight.
Skipping the kitchen area makes the whole cage dirtier and increases your cleaning workload. Spend the five minutes to set up a designated food zone. You will thank yourself later.
Building a C&C cage is genuinely one of the most satisfying guinea pig ownership experiences. You end up with a cage that is custom-sized, affordable, and expandable — and watching your pigs popcorn around all that space for the first time makes the hour of assembly totally worth it.