How to Make Custom Storage Furniture from Cardboard

I am a bit embarrassed to share this post, because I haven’t actually finished surfacing my custom shelving unit, but it’s been more than a year since I installed it, and… well… at this rate I may never finish it. But here’s the story of how I built a custom shelving unit in my apartment using cardboard, craft paper, wood glue, and bits and bobs.

How to Build Custom Cardboard Storage Shelving

I have ZERO storage in my studio apartment, and had an awkwardly-placed niche in the wall, so I decided to build a storage unit in the space.

Designing Custom Cardboard Storage Furniture

The space I had to work with is 213 cm tall and 173 cm wide, but only 26 cm deep. I wanted to create a place to hang clothes and bags, since it’s near the front door and could act as a coat rack, and also a shelving space to store books and display knickknacks. Because it’s such an odd-sized shape, I couldn’t find any premade shelving units that were the right size, and I couldn’t afford to hire someone to make custom furniture for me. Here are some of the things I wanted from this construction:

• I didn’t want to split the area in half; instead, I wanted the centerline offset to match up with the foot of my bed
• I wanted the shelf surface on the “bed side” to be about the same height as the bed, so I could use it as a night stand/end table
• I wanted to add rods for hanging clothes, and a small shelf with drawers in it for sunglasses and whatnot
• I decided I needed an opening in this “shelf” top so that my long coats could hang down through it, rather than pooling on top

In addition, I had to consider things I have learned from other cardboard construction projects, so let’s digress a bit for those:

DIY Cardboard Paper Craft Supply Organization

Okay, so this isn’t exactly “organized” now, but it’s precisely sized with three shelves for A4 paper, and then a vertical bin in the rear to store paper rolls. It’s surfaced with craft paper for the body, and fiberboard for the facing, which I painted grey. It’s perfectly strong enough to do the job, but the top is too thin/doesn’t have enough support, and sags. 🙁

DIY Cardboard Craft Supply Tower of Terror

This was designed to maximize vertical space, since I have a small desk and high ceilings in this apartment. It’s made from cardboard, covered in craft paper, surfaced with grey fiberboard to match the paper organizer. It’s designed with shelves that get progressively shorter as they get higher, and organized so that the things I use most often are clustered at the bottom right, while things I use less often are placed higher and further away.

One of the things I like about this piece is that I made the highest shelves the correct height for the jars, containers, and pots I need to store, and I added small rods inside some of the cubbies for ribbon, tape, and whatnot. The one problem with this design is that I built it to fit into the corner exactly at a 90° angle, thinking it would be supported by the walls and therefore didn’t need to me to build/create a lot of support. However, once I put things on it, the weight pulled the entire structure more toward the center – you can see that the top left corner doesn’t meet the wall at all. However, it seems sturdy and stable anyway, and doesn’t wobble or anything, so I got away with a pretty major design flaw.

DIY Cardboard Cubby

I’m not sure what you would call this object, but it was my first attempt at making a working drawer out of cardboard. The cardboard was cut precisely to fit, and it DID fit, but once I started layering on the finishing paper, the fit got tighter and tighter. So then I had to shave down the top of the drawer sides to make the drawer move more freely, which made them ugly, so then I had to cover them with paper, which added more height, and so on. It moves now, but it’s a bit tight with a spot of resistance, and I learned a lot about making drawers.

Okay, now, back to the good stuff

Building a Cardboard Shelving Unit

With all that in mind, I knew that my design had to consider:

• Weight. I knew I wasn’t going to load it up with anything especially heavy, but that there might end up being a lot of cumulative weight. The bottom shelf on the “bed side” has an old computer stand beneath half of it; this allows that lower shelf to be strong enough to support books. The other shelves were made strong, but probably not strong enough to be bookshelves.
• Flatness. I knew that my construction methods would probably be sloppy enough that things wouldn’t be completely level, but that if the shelves sagged in the middle, they might pull away from the edges, where the weight is supported. The shelves needed to be not just strong, but flat.
• Pressure. I wanted to make the shelves, if possible, push against each other. If they could push toward the center and outer support pieces, then they would work together to hold the center vertical and keep each other in place.

With all that in mind, here’s a rough diagram of how I designed the piece:

If you take a closer look at the vertical pieces, you’ll notice that there are three tall, fairly strong pieces at the center and sides. But then every shelf is supported by shorter vertical pieces that are bound to the longer vertical pieces, and the shelf edges are sandwiched between these shorter vertical pieces.

The way I made this is:

• Longer framework pieces: I took six pieces of cardboard and cut them to 213×26 cm. These six pieces would form the outside of each of the framework segments. I laid down one of these big pieces and then layered more cardboard on top of it, gluing progressive layers of cardboard onto the big piece. These “interior” pieces could be smaller, and they are more like a patchwork of pieces of cardboard laid down in a single layer, glued into place, and then trimmed to size. To create greater strength, make sure that your cardboard alternates direction, with corrugation running both ways or different ways, so it doesn’t “want” to bend on the same axis. As I glued every layer, I laid heavy books all over it and let it dry flat before adding another layer. When the outer pieces were 2cm thick, and the inner one was 3cm thick, I glued down strips of craft paper, wrapping each piece completely for added flatness, strength, smoothness, and a better glue surface for subsequent additions.
• Installing the framework pieces: I then installed the framework pieces. I used small corner brackets and construction adhesive to “pin” them to the wall, just so they could stay in place while I kept building.
• Shorter vertical support pieces. Then I would measure the height I needed for a vertical support piece, and cut a piece of cardboard to fit that. Then, as above, I added layer after layer of cardboard, building it thicker, criss-crossing the direction of corrugation. As above, I often used smaller individual pieces of cardboard, just gluing them down, drying them with books on them, and then trimming the edges flush with the layer below. When the vertical support pieces were 3-4 cm thick, I added strips of craft paper, gluing them down and wrapping the piece completely.
• Installing the shorter support pieces: Each vertical support piece was glued to the correct vertical framework piece, and then I used strips of craft paper and glue to really secure them in place, bond them together, and cover the front gap where they met. I did this on both sides. For example, for the center, I would install a vertical piece on the left of center, glue it in place, then glue down strips of craft paper over everywhere they joined. Then I would install a piece to the right of center, glue it in place, and then glue down strips of craft paper over the entire center column, so the outer layer of paper covered all three pieces.
• Building horizontal shelf pieces. As you can expect, I made the horizontal shelf pieces the same way. When I had two support pieces installed, I measured and then cut cardboard the dimensions of the shelf. I then layered cardboard pieces on top of it, building it up to 3-4 cm in thickness, then gluing it all together with strips of craft paper.
• Installing the shelves. As you may expect by now, I would then install a horizontal shelf, gluing it in place (and I buried another little metal shelf bracket in these joints, for added support and to try to prevent sagging) and then covering the whole joint in craft paper.
• Building another vertical piece. Once I had a horizontal shelf installed, I measured, cut, built, and installed another set of vertical supports that would sit on top of the shelf piece and hold it in place.

So I went on like this, building it from the bottom up, and using every new piece to further reinforce and secure the one before. I like this method because it meant that I didn’t need to make everything all at once and install it all at once: I could make every piece as needed, and just keep working on it. In fact, it took months.

For the drawers, I basically just made two shelves as described above, cut a hole in them for the coats, then made the drawers to fit. Then all I had to do was add a front panel and panels around the hole to turn the two shelves into a box, and then make fronts for the drawers. I used store-bought drawer pulls.

Finishing a Cardboard DIY Shelving Unit

Okay, so it ISN’T finished, but here are some thoughts about that:

Before I began, I painted the interior of the niche dark grey. Having the shelves and the rear wall dark grey, with white on the front facing, creates the illusion of greater depth. Dark colors recede, while bright colors move forward. Because it’s just 26cm deep, I wanted to visually enhance the depth.

As much as I love simple glued craft paper as a finished surface, I didn’t want it here. I wanted something tougher and easier to clean. I bought dark grey vinyl contact paper and used it for the top of the shelves and some of the framework pieces, so they can easily be wiped clean. The vinyl contact paper matches the shade of grey that I painted everything, so it doesn’t stand out.

I already had those curved wooden shelf brackets from some floating shelves that I had taken apart. They are inset into the cardboard vertical support pieces, so they support the shelves from below and are integrated into the construction, rather than sitting on top of it. My hope was that they would help to keep the shelves flatter, although that doesn’t seem to be an issue so far.

I haven’t finished adding the white facing to the front. I thought to use white paper, so I wouldn’t have to tape off and paint after the fact, but didn’t like the white paper I had on hand, and tried a few different kinds, and ultimately ran out, so…. here we are. My current plan is to get some thin white foam core and use it to finish and unify the front face of the piece.

Principles of Building Custom Cardboard Furniture

When I build cardboard pieces that need to be strong and support weight, here are the core principles:

1. Create a framework. The external framework needs to be rigid and accurately sized, but it does not itself need to support weight. It serves as the attachment point for the strong pieces.
2. Build strong support pieces. Within the framework, add thick, strong pieces that will bond to the framework outside, and support weight on the inside.
3. Use layers of cardboard with crossed grains. Build your strong cardboard pieces with many layers of cardboard, until the piece is at least 3cm thick. Alternate the direction of corrugation to create strength and avoid a tendency to bend or sag.
4. Use glue and paper to bond the pieces together. When joining pieces together, use glue to adhere them. Then join the joints and edges with strips of paper glued over the seams. Then wrap the joints with more glue and paper to create extra strength and stability, and unify the structure into a single piece. Do this every time you attach pieces together.
5. Start small. If you are new to working with cardboard, make something small and simple, so you get the hang of it. Make a small cabinet with a drawer, or a small shelving unit, so you can learn more about how to build with cardboard and manage weight and pressure.

With good measurements, a lot of glue, and a lot of cardboard, you can create almost any custom storage or shelving you need. And then check over here to see more about how to finish the external surface so it looks nice.