I found a large shipping wood pallet that was heavy-duty and which was perfect for this build of my Ladderchair/Librarychair. First, I cut off all slats and de-nailed the slats. The frame of the pallet was 2×4×6 and I cut them down to 2×3 to cut down some of the weight. After finalizing my design of the frame, I drilled some pocket holes and added 2-inch pocket screws covered with pocket dowel covers.
I also cut some slats for the bottom steps and leaving a few of the 2×4 for the top step where most of the support was needed. I had to purchase a chest continuous hinge for the ladder chair to open freely.