My experience with masonite for inner covers is that it tends to bow downward if you use top feeders. I don't like using masonite personnally. BE>I plan to mke my own hives. BE>1. Does anyone have any thoughts on the use of Masonite for the Inner cover BE>and the hive top (tin clad). BE>2. Any problems with the use of treated timber for hive boxes? BE>John Lewis BE>Fiji