A building panel has an outer skin spaced from an inner skin, sandwiching an insulation material. A first end of the outer skin includes a step portion, an indented fastener receiving portion and a first flange. The first flange extends outwardly toward a surface of the outer skin. A seal is mounted on the first flange. The inner skin includes a first end. The inner skin first end includes a shelf and a second flange extending from the shelf. A second seal is positioned on the second flange. A second end of the outer skin includes a portion to receive an outer skin first end of an adjoining panel. A second end of the inner skin includes a portion to receive an inner skin first end of the adjoining panel.