Wall panel

A method of forming a wall panel system for a building structure, the method comprising:

• (a) providing a plurality of wall panels, each of the plurality of wall panels comprising:
• a rigid magnesium oxide layer having a first side and a second side, the rigid magnesium oxide layer having glass fiber reinforcing material embedded therein, wherein the rigid magnesium oxide layer has a matrix consisting essentially of magnesium oxide that retains the glass fiber in a desired location and orientation;
• and
• a foam layer on the second side of the rigid magnesium oxide layer;
• (b) securing each of the plurality of wall panels to a structural element;
• and
• (c) applying a sealing compound onto seams between the respective wall panels on the first side of the rigid magnesium oxide layer.