Stairway or ladder?

Hi to everybody,
Today I’ll show my new design. This design is the mix between a normal stairway and a ladder, in fact, as you can see, is a folding stairway.

When it is unfold it can look like a normal stairway. It’s big enough, and you can use it pretty comfortable.

But when the stairway is folded, it’s almost invisible, andit takes up less than a normal ladder.

You have the advantages of one stairway when you must go up and go down, and you have the advantages of a ladder when it’s folded, it takes up very small space, no more than a big-picture hanged in a wall.

You’ll see in the next pictures, the stairways when is folded. It only takes up less than 50mm in deep. It is completely plain, the treads are totally aligned and vertical.

Now begin to unfold the stairway, the treads begin to rotate to his position.

Finally, the stairway is completely open, and all the treads are horizontal, parallel with the floor.

All the treads are the same piece, but is not joined by the same way.
The treads are joined by rotated ones from others.

This step design is for one clear reason, it’s for have more tread footstep and, although the stairway are very sloped, you have more than enough space for going up.