I don't know your model, but I'd suspect the hull is the hull and, once decked, the bulwarks are situated just inboard of the deck edge planking, extending upwards.
Do a Google search on pilot cutters - it'll probably make more sense than my opening sentence!
Belay that comment! Is this the Sarik plan? That appears to show the bulwarks outside the decking's margin planking, and inline with the hull surface. There's a wee gap between hull side and bulwarks for the water to get out, the bulwarks being held in place by those square posts. And on the 'chainplates' drawing there's evidence of wood fillets showing the bulwarks and hull surface inline.
Andy