A rope ladder is a vital component of any treehouse or sailing vessel. While the classic Jacob's ladder, with wooden rungs, is both easy to construct and easy to climb, storing it can be a bit of a problem. When rolling the ladder up, you'll find that all the wooden rungs make for a fairly large bundle, which limits the places you can store it. If you need a more flexible, easily-stored ladder, make one out of a single piece of rope, following an old traditional pattern.
Construct a jig to help you space the rungs evenly and keep the rope taut while making the ladder. Drive four nails halfway into a piece of plywood, positioned to form the corners of a rectangle 6 inches wide and 16 inches long. Add a fifth nail half an inch below the lower left corner. The nails should stick out enough above the board to be able to wrap the rope around them.
Measure the length of rope you'll need. It should be twice as long as the ladder, with three extra feet of rope for each rung. Count enough rungs so that there will be one every 16 inches along the length of the ladder. Cut the rope to length, leaving a few extra feet to be safe.
Find the midpoint of the rope and wrap it around a thimble. Secure the rope to the thimble with a seizing of twine, wrapping the twine first several times around the two ropes and then around itself between the ropes. Hang the thimble over the top edge of the jig, with the two legs of rope hanging down in front.
Wrap the left leg of the rope under the first nail in the lower left corner, around the right nail and then around the second left nail, pulling the rope out toward the right.
Put the right leg of the rope through the upper loop and under the lower loop. Wrap it around both loops repeatedly until you reach the left side. Here, slide the leg under the top loop and out through the bottom loop. The right leg now becomes the left leg and the left leg, the right. Reposition the rope on the jig, with the rung you just created resting on the top two nails.
Repeat Steps 4 and 5 until you've wrapped as many rungs as you planned, nearing the end of the rope. Finish the ends of the ladder with a splice or whipping, or leave them loose, as you prefer.