When your shed or other storage building no longer provides enough room, you can add additional storage if you add a lean-to onto a shed. if the existing shed is structurally sound and has an exterior wall to which you can attach your lean-to, adding a lean-to can be a fairly simple project.. It isn’t a requirement that this shed be built against a wall—but the structure is designed to take advantage of the wall for strength. so if you modify it to be a freestanding shed, you’ll need to build a conventional stud wall across the back and face it with the same type of plywood siding used on the rest of the shed.. Afterwards, you have to build the back wall of the lean to shed and to install it on the flooring, in the same way described above. as you can see in the image, you have to cut the top of the wall studs at 17.5
