natural light also played a major part in the design. in the drafting room, wright used translucent canvas to act as a roof (later replaced by plastic because of the intense wear from the arizona sun). in the south-facing dining room, wright did not take the masonry walls from floor to ceiling, and designed the roof to hang past the walls preventing unwanted sun rays from penetrating but allowing for horizontal light to pass through the room. wright believed natural light aided the work environment he had his apprentices in, keeping the inside of his building in touch with the natural surroundings.