PURPOSE: To both absorb an error of dimensions in a flange part and perform replacement work only of a fender part susceptible to damage, by mounting an L- shaped gunnel member to the upper edge flange part of a ship side and equipping a fender material to an external ship side adjacently to an outer end part of said gunnel member.

CONSTITUTION: In the upper edge of a ship side (b) in a small ship made by fiber reinforced plastics (FRP), a flange part b1, protruding to the inside of the ship is provided, then to an upper edge of the flange part b1 a gunnel member 1 of L- shaped section is mounted. A side part 1a of the gunnel member 1 in th inside of the ship is suspended from an inner end of the upper edge of the flange part b1, while an outer end 1b of the other side part is protruded to the outside of the ship from an outer end of the flange part, then adjacently to an outer end part of said gunnel member a fender material 4 is equipped to an outer face of the ship side. In this way, an error of diemensions in the flange part b1 of the upper edge at the ship side can be absorbed simultaneously replacemenet work only for the fender part 4 susceptible to damage can be performed.