: So my question is, is this a foolish thing to be considering? How important
: is that extra quarter inch? Would a thicker coaming lip somehow be a
: problem? What about the non-marine aspect? I don't envision the coaming
: getting persistently soaked, but then again, I don't have enough
: experience to know what to expect.

A 1/2" coaming lip looks a bit odd. I recommend 1/4" per the manual. In
reality, not all 1/4" ply is created equal, meaning that some 1/4" is
actually 3/16" or less. The thinner I can find the better....up to a point.

In order to do so, I sometimes use 1/4" interior grade ply from Lowe's which
comes in 2' X 2', 2' X 4', or larger sheets. Interior grade often has fewer
plies, and the glues holding the plies are not exterior grade quality. Be
sure to coat with epoxy per the instructions.

As I recall, the single chine Sea Bee from the instructions has an all
interior grade "Aspen" ply coaming simply because I liked the look of
the Aspen plywood... and it was cheap. It has held up just fine.(pic attached)

Tom