Spence,
When I bought my house 4 years ago, the old owners had that corrugated plastic put in place under the deck to store their sports car. Thusfar, it works great. Diverted to a gutter hung on the deck, it is pretty waterproof. Only problem is that in heavy rain, so much water pours out of the plastic, it blasts past the gutter and splashes under the deck. I was going to put another piece in the ground to divert that problem but built a shed instead. More room = more toys!!
