Abstract: An integrated, compartmentalized, water impermeable hull that is constructed of a plurality of lengthwise tubes. The tubes are arranged in a generally parallel relation to one another such that an outer surface of each tube abuts an outer surface of at least one other of the tubes. The tubes are sandwiched between a first inner support layer and a second inner support layer. Each inner support layer undulates along and fixedly adheres to the tubes to thereby hold the tubes in a fixed relation to one another. First and second outer support layers are positioned over the first and second inner support layer, respectively, and are fixed to a plurality of peaks of the first inner support layers to thereby reinforce the first inner support layers.