Ching talks about concrete, steel, and wood floor and roof systems and how they are supported by and tied to different types of masonry bearing walls. He talks about stone and how natural stone is a durable, weather-resistant construction material. Which may be laid in mortar to make bearing and nonbearing walls. He also talks about different windows and explains certain parts of it. For example, sash and glazing. Sash is the fixed or movable framework of a window. Glazing is the panes or sheets of glass set in the sashes of a window. Pane is one of the divisions of a window, unit of glass set in a frame.