plywood floor

Pete,

Scarfing isn't in my carpentry dictionary at this point. I will attach a 1x4 cross piece at this point only to support the joint.

Im referring to the 1x3 pieces between the main and secondary stringers as the cross pieces. Basically Im being lazy and don't want to notch the stringers for them, plus they are redundant if you span the plywood cross ways.

The only way they would be required is if cantilevered out to pick up an edge support for the floor at the hull. When attached, the plywood provides continuous lateral bracing of the tension face of the stringers (when the stringers are loaded from the water side), which I feel makes the stringer system as strong or stronger than the original foam and fiberglass system around the stringers. The plywood provides greater floor diaphragm strength than the fiberglass (basically it's a stiffer floor)

When the stringers are loaded from the top by people and the motor, then the hull braces the tension face of the stringer laterally. Same as the original design in this case. Anyway, that's my thoughts on the plywood floor from a stringer structure standpoint.

Unless Im missing the way the boat sees the forces.

JDiggs wrote: When attached, the plywood provides continuous lateral bracing of the tension face of the stringers (when the stringers are loaded from the water side), which I feel makes the stringer system as strong or stronger than the original foam and fiberglass system around the stringers. The plywood provides greater floor diaphragm strength than the fiberglass (basically it's a stiffer floor)

Doesn't the hull provide support on both the top side and bottom side of the stringer due to the fiberglass wrap over the top? I definitely think your method would be stronger than factory either way though.

the discussions have always been about rot, not boats snapping in half, I think the hulls have the strength built in and the stringer systems adds to an already strong hull