Layout of Construction Drawings 141
Foundation Plan.
A foundation plan (Figure 6.15) is a plan view of a structure projected onto an imaginary horizontal plane
passing through at the level of the top of the foundation. A foundation sheet will indicate the size, thick-
ness, and elevation of footings (footers), with notes regarding the placement of reinforcing bars (rebars).
It will typically note locations for anchor bolts or weld-plate imbeds for structural steel and other ele-
ments. The footing schedule is normally found on the first sheet of the structural notes, which also in-
cludes notes regarding the reinforcing requirements and other written statements for structural strengths
and testing requirements. To be able to properly interpret a foundation plan, you must first view the other
plans, such as the sections and roofing plan.
The foundation plan shown in Figure 6.15 tells you that the main foundation of this structure will con-
sist of an 8-inch masonry stem wall, centered on a 24-inch-wide by 12-inch-deep concrete footing rein-
forced with three #5 bars. The width and depth of the concrete footing will vary according to location.
The drawing also shows a 4-inch-thick concrete slab reinforced with welded wire mesh. Besides the out-
side wall and footing, there will be two 30-inch-, 36-inch-, or 40-inch-square concrete footings reinforced
with three #5 bars in each direction. From the drawing we can see that ½-inch-by-10-inch anchor bolts
are used at 32-inch centers typically located on the building’s perimeter.
Framing Plan.
The framing plan will indicate the material used for framing the building and may include wood or metal
studs, concrete-masonry units, or structural steel. Framing drawings include the basic skeletal structure
of the building and are drawn to scale. Floor-joist locations, walls, and roof trusses are part of the over-
all detail of these plans. Generally, locations of each stud are not included, since the process is stan-
dard. However in some cases there are instructions for particular wall-construction methods.
Intermediate structural framing plans are used for multistory construction, where each level may re-
quire support columns, beams, joists, decking, and other elements. Structural drawings also typically in-
corporate numerous details relating to the structure. Figure 6.16 shows typical examples of structural
details.
6.5 MECHANICAL DRAWINGS.
The cover sheet for mechanical drawings should contain appropriate notes, legends (chart or table of
symbols and abbreviations), and details. The mechanical plan specifies the design of or the modifica-
tions to the mechanical system, ductwork layout and dimensions, mechanical equipment location,
damper locations, design air-delivery rates, diffuser locations, thermostat locations, and supplemental
cooling systems if required. Mechanical plans are normally identified as M-1, M-2, M-3, etc. Some con-
sultants prefer the heating, ventilating, and air-conditioning drawings, commonly referred to as the
HVAC drawings, to be sequentially numbered and prefixed by the letter “H”; the plumbing drawings to
be prefixed by the letter “P”; and the fire-protection drawings to be prefixed by the letters “FP.” Most of
the work shown on these types of drawings is in plan view. Because of the diagrammatic nature of me-
chanical drawings, the plan view offers the best illustration of the location and configuration of the work.
Due to the large amount of information required for mechanical work and the close proximity of pip-
ing, valves, and connections, the engineer utilizes a variety of symbols and abbreviations to convey the
design intent. Examples of these symbols and their meaning can be found in Chapter 8.