Abstract: A building system includes a plurality of panels. Each of the panels includes a plurality of studs configured to serve as structural members and a polymeric block including a structural layer defined by the width of the studs and an offset layer. The offset layer extends in an interior direction from the structural layer. Upper and lower lengthwise notches may be included in the offset layer of the polymeric block. Non-structural elements are installed in the upper and lower lengthwise notches for use in mounting interior elements (e.g.