Our pen is 10 x 16. I placed 10 footers across the pen every 5 or 6 feet, and midway on those I sistered three 2x4s as supports. They just sit on rocks or concrete pavers, and are screwed to the 10 footers. That supports the woven wire fence I have across the top of the pen. It works well so far. I used 1 inch diameter washers with little holes in the middle to attach the woven wire fence to the tops of the pen and the 10 footers. That has also held for more than 3 years. Snow does not pile up on it. It does pile up on the light fabric I have pulled across the top, though, to keep me from having to shovel out the pen. And that seems to be no problem, either. We have had about 18 inches on top and it held fine.