Would it be possible to build a multi level cardboard fort??

Question

if you used interlocking cardboard for walls and the ceiling/floor (walls and floor would be about 4-6 inches thick) to support the weight on the second floor

Answer 1

Well, I'm not going to say its impossible. I think the cardboard would hold up fine at that thickness but I forsee two problems:

1) The weight of the second floor compared to the carrying capcity of the first floor

2) Your adhesive will need to be really strong

Solve those two problems by

1) Building sturdy, strategic supports

2) Investing in some strong adhesive from the hardware store.

Answer 2

Use a box construction for the floor. Try this experiment. Take corrugated cardboard about 36" X 16". fold it 3X to make a square tube 4" X4" X36". tape the seam and hold it up on the ends and see how much weight it will support. Should be pretty strong.

Keep in mind that a longer tube won't support as much weight as a shorter tube.

You might find that 1" or 2" tubes in alternating layers might be preferable.

If you don't want the tube and and only flat cardboard keep in mind that the strength comes from cardboard mounted vertically not flat. so strips the are vertical will give a lot more strength. Place a flat piece on top for the floor. Corrugated cardboard will be stronger if the ends with the wavy cross section are at the top and bottom edges than on the sides.

Be sure to get plenty of fire insurance!

Answer 3

Maybe if the wall were solid cardboard, as in layerd glued together.  You would defiantly want an arched ceiling and buttressed walls.