Weighty Matters

I calculated the weight the cold frame would have been subjected to.

Given that the weight of water in pounds per square inch is 0.036127, here is what the water on the ribs might have been:.

Depth   Weight outer ribs   Weight center ribs
1 inch                     23.41               46.82
1.5 inch                 35.12               70.23
2 inch                     46.82               93.64

I cut out some snow and found that, after some melt, there was about an inch of water that would have accumulated on the top of the cold frame. No wonder it collapsed.