A corner assembly comprising an elongated main portion including a central section opposed by first and second lip sections, with the first and second lip sections extending laterally from the central section. The corner assembly additionally comprises first and second flange sections extending generally laterally from the central section, with the first flange section extending generally parallel with the first lip section and the second flange section extending generally parallel with the second lip section. The first flange section is separated from the first lip section so as to present a first receiving channel and the second flange section is separated from the second lip section so as to present a second receiving channel. The corner assembly further comprises an elongated cap section operable to be securely positioned over the elongated main portion.