We have a loft in our new house and we've been struggling with a solution for a ladder up to the loft. The loft is at the start of a hallway, so we have a width of 105 cm to work with. The floor of the loft is 262 cm up. I drew about 15 different possibilities with ladders that fold up (none would work in the space requirements) and ladders that slide down (complicated, requiring 3 parts and special rails for the slidy parts).
In desperation I googled "clever folding stairs" and browsed through pictures, and then found a concept that I loved. It works beautifully, folding to the side to take just 16 cm of hallway space and folding out to a sturdy stair case with 45 cm wide steps, a comfortable angle, and taking you up in the proper direction instead of a ladder against the wall. Here's the result. Still needs to be stained.
Just a heads up, that these are not very safe. Each step/rung is only held up by the grip of the screws in the hinges. A safer design would have each step / rung resting on top of some kind of block that is supporting the user's weight.