My office has used the NCS since its inception. As Eric said, it is a guideline to follow and is completely customizable to your needs.
Also be aware that NIBS is currently working on a National BIM Standard. I am currently involved with the NBIMS committee, and the NCS will most probably be utilized in the future NBIMS.
David Larrew, AIA, GDLA, GSRC
Architectural Technology Specialist
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