The present disclosure provides a system of light weight folding stairs, especially lightweight wooden stairs, designed for installation in the ceiling of a building. For example, the light weight ladder-type stair system may be opened downwards and unfolded towards inside the room located under this ceiling. At least one ladder-type stair section is connected to a flap that fits within a frame in an opening in the ceiling, wherein the flap hinges open to access the folded stair sections. The ladder-type stair section is connected to the flap by a hook-type holder that allows installing the frame in a ceiling opening without the flap, which can be easily and quickly attached during final stage of assembly.