We have a square cut out in the ceiling pretty high above our stove where it looks like the previous owners were going to possibly install a chimney range hood. However, below the square hole, they had hung a pot rack where we currently store all of our pots and pans. The hole is getting really dirty and grimy but we aren't sure we can just drywall over it? It must vent up to the attic somehow although that is 2 floors up. Wopld it be dangerous to just wall it up or should we try to find some sort of cover that would still allow it to vent but cover the ugly appearance of the gaping, dirty square hole?