136 Chapter 6
Examples of building sections can be seen in Figures 6.13A and B. Figure 6.14A represents a sec-
tion through a staircase drawn to a 3/8 inch = 1 foot, 0 inches scale. Several different sections may be in-
corporated into the drawings. Sections taken from a plan view are called cross-sections; those taken from
an elevation are referred to as longitudinal or simply wall sections. Figure 6.14B shows a typical wall sec-
tion. This type of section is commonly drawn at a scale of 3/4 inch = 1 foot, 0 inches. It is normally located
in the structural division and provides information that is necessary to understand the structural arrange-
ment, construction methods, and material composition of the walls of the building. Using sections in con-
junction with floor plans and elevations allows the reader to get a better understanding of the project and
how it is put together.
Sections are used as needed in each of the main divisions of construction drawings to show the types
of construction required, the types and locations of materials used, and the method of assembling the
building parts. Although they may be used in each of the divisions, the most common are the architectural
and structural divisions. All sections are important to those responsible for constructing a building.
6.4 STRUCTURAL DRAWINGS.
The structural drawings provide the reader with a view of the structural members of the building and how
they will support and transmit its loads to the ground. Structural drawings (often referred to as “struc-
turals”) are sequentially numbered beginning with an “S,” as in S-1, S-2, S-3, etc. They are normally lo-
cated after the architectural drawings in a set of working drawings. For new construction, structural-en-
gineering drawings will be needed for foundation and footing details, the structural frame design, beam
sizes, and connections. In concrete structures, the structural drawings will indicate concrete forming de-
tails, dimensions of members, and reinforcing-steel requirements. If the structure is steel-framed, the
size and type of steel framing will be indicated.
The benefit of structural drawings is that they provide information that is useful and can stand alone
for subtrades such as framers and erectors. The structural drawings clearly indicate main building mem-
bers and how they relate to the interior and exterior finishes without providing information that is not nec-
essary for this stage of construction.
Structural drawings, like architectural drawings, start with the foundation plans, ground or first-floor
plan, upper-floor plans, and the roof plan. The main difference is that only information pertinent to the
structural systems is shown. For example, a second-floor structural plan would show the wood or steel
framing and the configuration and spacing of load-bearing members but not doors or non-load-bearing
partitions. Following the plan views are the sections and details in the same basic format as in the archi-
tectural drawings. Schedules are used to record such information as footings, columns, and trusses.
Types of Foundations.
Houses and small frame buildings do not need complicated foundation systems. A simple inverted-T
foundation is all that is normally needed to support the structure under normal conditions. Larger and
more complex buildings impose a heavier burden on the foundation system and need to be carefully
designed by structural engineers. Foundations for large commercial buildings perform the same func-
tions as those for light-frame structures. The main difference in the foundations for a commercial
building and that for a small residence is often the thickness of the concrete and the amount of rein-
forcing steel.