Here is my summer vacation project: I want to redo an old garage roof by replacing the old tongue and groove boards with sheets of regular plywood (not marine grade) but I do not want to re-shingle. Is there a modern day coating that I can just roll onto the plywood that will seal the roof and make it waterproof? Hopefully , if the answer is yes, I can buy this coating at Home Depot or Lowes :-) I don't care what the roof looks like,i.e.; the coating can be black or any other color.
What you can use is roll on roofing, here's some information. The issue with a coating, like a thick paint type of thing, is that joist in the plywood sheathing, there will be differential movement, especially in the vertical direction (in and out of the sheathing face).