Hello I have a question on a basement that is under a partially covered carport. This is new construction it was having leaking issues so we jacked out the concrete and pulled the pan decking. My waterproof contractor is telling me to change the pan decking to 1 1/8 inch tongue and grove plywood and hotmop it with a #5 rebar 12" square grid with 4 inches of concrete on top. All this is sitting on 6" by 12" high glulams 10" on center. All of this is because my contractor is saying that it is almost in possible to waterproof the sides of pan decking. Any help or ideas or input is very much appreciated.

Thanks