A joining member for mechanically joining a skin to a supporting rib has a first surface and a second surface opposite the first surface. The first surface is adapted for bonding to a surface of the skin via a layer of a first adhesive material. The second surface includes a groove having an inner surface adapted for receiving and bonding to an outer edge of the rib via a layer of a second adhesive material. The joining member enables a novel method of construction having advantages over the prior art.