Re: Straw Board for a Pontoon Deck?
Keep in mind that the wood on the deck is a major structural member of the boat, it is what gives it its rigidity and the underside of the deck is constanly being sprayed hard with water kinda like a fire hose so no way would I go with any kind of particle board no matter what they say it will do, "water resistant" is fine it gets a bit of rain mist on it now and then but deck wood is constantly soaked.
He may save money up front but will be redoing it next year so tell him to save his pennies and do it right or do it again.
Go with a good exterior grade 3/4'' ply seal it good and seperate it from the crossmembers and you won't touch it for years.