We have been making CEBs one weekend and then laying them over the next few weekends, which means we needed a way to safely store them. We stack them on pallets and then cover them with tarps and metal roofing. Our tarps are old and have some small holes, and if that hole happens to be at a gap in the blocks, a valley will form that collects and drips large amount of water to the blocks below. The metal roofing protects against the rain and the tarps ensure that the blocks dry slowly, which is good for their strength.