Design Documentation: Drawings and Specifications
419
specifications complement each other. Drawings usually identify
quan-
tity,
specifications cover
quality.
There is no legally prescribed format for technical specifications.
Any presentation of information which gets the contractor to do what
the owner wants in a timely and cost effective manner can be consid-
ered a good specification. Decades ago, virtually every office had its
own arrangement for specifications. Different components of construc-
tion could be found in almost any order, and the verbal expression
could take almost any format. Roughly since World War II, there has
been a gradual but discernible trend toward what is now a highly
sophisticated and almost universally accepted arrangement for pre-
senting technical specification information. The general format can
probably be attributed to the federal government in its several agen-
cies which oversee construction of thousands of projects.
As background for specification organization, recognize that many
different trades may work on a single project, but for clarity and ease
of bidding and quality control, it is helpful to group work for a given
trade in one area or section of the specification. At the same time,
recognize that a single contract between the owner and contractor for
many elements of work creates a commitment for the contractor for
all work, whether it is well arranged or not; but it may be difficult for
the contractor to apportion work between trades, between subcontrac-
tors, if the specification is fragmented.
The format which has gained general construction industry accep-
tance has 16 divisions for major categories of work. These divisions
are listed in Fig. 13.2. Each division is broken down into sections with
as many sections and as much depth as needed to convey the criteria
for the work (see Fig. 13.3).
Each section in turn has a format containing three parts, as indi-
cated in Fig. 13.4.
As stated before, specifications can be written with more or less
detail as desired. Specifications for residential housing are often ab-
breviated to 3 to 5 letter-size pages for the whole house, relying on
the habit of the contractor for most detail. In contrast, specifications
for large buildings contracted for through competitive bidding, which
requires tight quality control, may be several hundred pages long.
Where many small items and work descriptions are involved, they
may be lumped together in a single section. A major component which
requires much detail to describe, such as a chiller or a boiler, may be
given its own section.
The organization of specifications as described above leads to a file
full of specifications for every imaginable product and construction
method. To the extent that the writings are generic, they become
mas-
ter specifications
and can be referenced over and over from one project
Design Documentation: Drawings and Specifications
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