Cardboard Chair FAQ

The cardboard chair is one of the most popular items on my web page. I fairly frequently receive email asking me how to make the chair, which previously I've had to decline since there were no written instructions or plans. The chair was designed in my head. Here is a `Frequently asked questions list' ending with suggestions on how to make the chair. I supply the information as is for those of you out there interested in making a cardboard chair or, as in most cases, those of you who have been told to make one for a school project. If you make one, please tell me how it goes (and credit me). The design is copyright but made available free for non-commercial use.

How did the chair come about?

The cardboard chair was made after I moved to New York with nothing but a 150lb shipping allowance. I had no furniture in a bare apartment just four cardboard boxes and their contents. After a while I realised that turning the packing boxes into furniture would solve the problems of their disposal and my lack of furniture. I had four packing boxes and wanted four chairs, so I made my design with the constraint that each chair had to be made from a single box.

Can the chair support someone's weight?

Yes. Certainly someone up to 180lb without problems. After a lot of use the first couple of chairs became very wobbly and were retired from service, but this version includes some design improvements that make it more stable.

Is there any other support to hold the person's weight?

The chair consists only of cardboard. The person's weight is supported by the cardboard. The design uses triangular beams of cardboard to transfer the person's weight to the vertical sides and thence to the ground. Beneath the beams is an empty space. The cardboard is fairly sturdy double-ply corrugated cardboard.

How is the chair held together?

There is no tape, glue or other fastener used in its construction. Natural properties of the cardboard are exploited (sturdiness, stiffness, springiness, friction, weight).

Can I get instructions or plans to make the chair?

There are some instructions and photographs of the parts below, along with dimensions. There is now a diagram to show you how I made the parts from the box, with more dimensions.

What tools do I need to make a cardboard chair?

I made my chair using just a pen to mark lines and a utility knife.

How does all that cardboard come out of a single box?

The seat is the lid of the box. The back is two sides with the corner of the box being the bend in the middle of the back. The sides are the two remaining sides of the box. The triangular beams come from the corners where the back meets the sides. One of these has the seam where the box was joined, so has two layers.

What happened to the bottom of the box that you didn't use in the chair's construction?

Well spotted. One-and-a-half box-bottoms were enough to make the recycled materials fruit bowl shown on another page. Other bottoms went to make a stereo stand of which I don't have pictures.

How do I make a chair?

The following provides some hints on how to make a chair. I apologise for the grainy photos that were taken with a cheap digital camera without enough light. The ruler shown for scale is 1 metre long, with markings in inches and centimetres. No attempt was made to make sure the photographs were taken from the same distance, so the scales of the photographs vary. There's some optical distortion, but I believe the pixels are square. On the other hand some shots aren't taken perpendicular to the plane shown.

Trying to copy my parts exactly probably isn't a good idea. You have to make the parts to fit one another. Obviously I can not be held responsible for any damage or personal injury incurred as a result of your trying to make or use a cardboard chair. Utility knives are dangerous things, and I can't be held responsible for any lack of structural integrity of any chairs resulting from even strict adherence to the suggestions below.

However irritating it may be, I strongly recommend that you read through all of these instructions and make sure you understand them before starting on construction. Pieces have to fit together and the reasons for a part being a particular size may not be apparent until later on.

Measurements

All the dimensions are in millimeters:
Seat panel: 480x480 (the base of the original carton) Some of this protrudes into the back, but this is the seat width.
Side panels 410x800
Back panel (when flat) 700 wide (fold in the middle) x760 high (in the middle, 775 at the edges)
Seat height 440
Triangular girders 650 long, sides ~70 .
Strengthening tabs about 50 wide by 115 long (when folded)
This may be more clear in the diagram.

Instructions

  1. First get some sturdy cardboard. The point of the chair is to be environmentally friendly though, so find some used cardboard somewhere instead of buying your materials.
  2. Cut out the back as a rectangle with the fold down the middle. Picture of back of chair
  3. Cut a very shallow V from the bottom of the back to cause it to tilt backwards. About 1.5" at the fold.
  4. Cut the sides. They are simple rectangles and will be mirror images of each other. Picture of side of chair
  5. Choose how high you want the seat to be.
  6. Cut slots in the bottom of the back parallel to the long edges to accommodate the sides. The slots should be less than the height of the seat chosen.
  7. Cut matching slots in the sides. These slots have to be at an angle to match the tilt of the back, and long enough to reach down to the top of the slots in the back.
  8. Cut the support beams and seat. Seat and beams of chair
  9. Fold the beams twice along their length to give a triangular cross section.
  10. Cut holes to receive the beams. The holes should be triangular with the top of the triangle parallel to the bottom of the side. The fit should be snug. The holes on opposite sides should be the same, but front and back holes might be different if your beams' cross-sections are not equilateral (As seen in my case.) Detail of holes for beams.
  11. Cut a slot in the back at the appropriate height to receive the seat. Note that as the back slants and is bent, the slot is not straight (the halves should be parallel to the `V' at the bottom, and should be symmetric. The slot will have to be wider than the seat thickness because it's oblique, and the distance of the slot from the bottom is more than the distance of the seat from the ground.
  12. Slot the back into each of the sides. Picture of chair with back and sides assembled
  13. Push the beams through the holes. Pushing them outwards from the inside, both through one side first should be easiest. Plan view of chair with beams inserted Elevation of chair side with beams inserted
  14. Slide the seat through the slot in the back from in front. The seat should be supported by the bottom of the slot and the tops of the beams. Detail of chair showing side, seat and both beams. Plan view chair side with seat inserted
  15. Cut arms in the sides according to your taste, comfort, artistic flair.
  16. For extra strength, this model of chair has additional supports made of U-folded rectangles of cardboard. These help to stop the back and sides moving relative to each other about the weak slot joint. For each of these, (there are four- one at the top and bottom of each of the side/back joints). cut short parallel slots in the back (side) so that one falls on either side of the side (back). Push the U-shaped piece through both slots when the chair is assembled, to strengthen the joint as shown below. Support tab inserted in the back around the tab of the side.
Back to the design page.
Andrew Senior
Last modified: Sun Mar 30 16:58:49 EST 2003