The invention relates to a supporting core composite panel (1) for internal enlargements, particularly for watercraft, having a supporting core (2) made of foam glass, having at least one cover layer (4, 4.1, 4.2), which largely covers the entire surface of the supporting core (2) on at least one side (2.1, 2.2), having an elastic adhesive material (3, 3.1, 3.2) that fastens the cover layer (4, 4.1, 4.2) on the supporting core (2).