There seems to be a couple of opposing views out there...mesh vs. no mesh: "Mesh" people thinking about the health hazards of standing, walking, laying, chewing, and licking their own waste....and "No Mesh" people concerned about toe and feet damage. From a builder standpoint, it would be cheaper to eliminate the lower level waste management system, replacing it with wood...however, the market for higher end rabbit hutches, chicken brooders, and small animal housing requires that the units are as maintenance free as possible. Additionally, I am often requested to install "pee shields" around the edges of the entire unit keeping the rabbits and small animals peeing on the walls. Some people put bedding material over the mesh. Our bunny actually scrapes the bedding away to lay directly on the mesh. To each their own and yes, I did build this unit.