: Hi Arthur,
: At 25 metres, (82 feet) in length, I think the scantlings would be in the
: range of 1 to 1.25 inch not including glass sheathing/reinforcement.
: (guesstimate, going by hulls I've seen)

: For something that length and beam, I think double-diagonal planking would be
: better with a schedule of lengthwise, diagonal, opposite diagonal,
: lengthwise. The outside lengthwise planks matches the lengthwise
: compression/extension forces, the diagonals counteracts the torquing
: forces.
: The diagonal planks might need steaming to bend around the turn of the bilge.

: Mike Savage
: South West Cork

Strip planking will work for a hull like that, just needs to be as you mentioned much thicker for the stresses involved. Also likely will need something like 12-18 ounce glass on each side, this is not a small boat.

Bill H.