"Wayne.B" wrote in message
...
On Tue, 20 Jul 2010 19:18:27 -0400, Larry wrote:

It's likely Trex if it's that old and that is recycled plastic and wood
fiber. It will certainly expand with the heat. The joists should be on
16" centers for the 5/4" boards. Closer (12") for commercial
applications.

Just my 2 cents worth but I'd be concerned about the weight. 3/4 inch
plywood is much lighter, probably less than half. Decent plywood
properly sealed with epoxy or good paint will last a long time.


My deck of PT ply with Nautolex lasted 15 years. Was not marine as did not
need the strength of no voids. I would use marine on a transom but not
necessarily on the floor. I replaced my deck with ACX PT. 5/8th I think.
But been a couple years.