ARCHITECTURAL WORKING DRAWINGS (sometimes identified with the designating letter A on their title blocks, as shown in chapter 3, figure 3-17) consist of all the drawings that describe the architectural design and composition of the building. A set of architectural drawings includes floor plans, building sections, exterior and interior elevations, millwork, door and window details and schedules, interior and exterior finish schedules, and special architectural treatments. For small, uncomplicated buildings, the architectural drawings might also include foundation and framing plans, which are generally included as part of the structural drawings.

A FLOOR PLAN is a horizontal section through a building, showing the outline or arrangement of the floor. An offset cutting plane is often required to pass through low and high features on the wall in order to reveal doors, windows, fireplaces, stair openings, and other features located in the building.

The floor plan is usually the first drawing worked on by the EA. It is considered the key drawing in a set of project drawingsthe drawing that all of the construction personnel will look at. Hence, the purpose of the floor plan is to show information about the location and type of construction, location and size of doors, windows, built-in fireplaces, stairs, rooms, and exterior and interior features.

Figure 10-12 shows the manner in which a floor plan is developed. Imagine that after the

Figure 10-12.-Development of a floor plan.

building has been constructed, a cutting plane is used and cuts through the structure passing through the plane WXYZ (view A) and that the upper portion has been removed (view B). You would then be able to look down on the floor from above, and the drawing of what you see would be the floor plan (view C).

Figure 10-13 shows a floor plan of a concrete-masonry construction. It gives the lengths, thicknesses, and character of the outside walls and partitions at the particular floor level. It also shows the dimensions and arrangement of the rooms, the widths and locations of the doors and windows, and the locations and character of the rest rooms and other utility features. Study figure 10-13 carefully!