Each hull section floats independently. Each are a closed, watertight, double-bottomed box filled with air that allows it to float. The thickness of the floor has been calculated so that the water is under the floor, even at the maximum permitted load (180 kgs).
Also, Reverso has a also self-bailing Cockpit . The deck has a slope to automatically evacuate any water that may enter the boat (waves). The water is drained in a few seconds through the large drains on the transom. There are joints between the sections, but they only serve to soften the contact between the 4 sections.