I've allways single stacked my rows. It really takes up alot of space because I leave about 10' between the rows for tractor access to gather up for burning, and room for snowplowing between (it snows in Maine) I'm about 15' into building my newest row and I'm double stacking it. Just wondering if there will be a huge diff in drying. This row is not for next year, and if I'm lucky not the year after either. The other problem that I see is covering it. I know some don't, but I allways put a sheet of roof metal on top of all my piles, right away. The metal is 37" and does a real nice job on my 26" single rows, it provides a nice overhang on each side, but will be short on my double stack row that is about 55+ inches. I'd need a lot more metal to fully cover the stack.