[Shop-talk] Keeping under a deck dry

[William M. Gilroy]

   I  have  a  10x20 deck that I would keep dry underneath so I can store
   things like the lawnmower, car fenders, old engines, etc.  You get the
   idea big stuff that I don't really need in the garage.  I was thinking
   some type of corrugated roofing material like this stuff  but made out
   of  translucent  fiberglass  so  it  will  let  some  light  in and be
   cheaper.   I  would run the stuff in 20 foot lengths with a  C channel
   at  the high end and some type fasteners or support on the low end and
   have  a  small  gutter  underneath.   Not  really sure how to hold the
   panels  together or build the support on the low end.  This would keep
   it dry and allow storage underneath.
   Anybody ever done this or have any better idea?
   Thanks,
   Bill in the rainy NW