Construction Drawings Sheet Numbering and Organization

In many cases, around the world, consultants and designers prepare construction drawings following their own drawing number standards, thus creating somewhat a confusion at the construction site. Many consultancy and design offices follow their own drawing numbering structure and refuse to implement a universal methodology, simply because this is how it is done for many years.

To this case, countries and standardization committees have prepared each their own drawing numbering structure and standards as a proposed solution to the case. For the last decade, we have seen several such national standards being prepared such as United States National CAD Standard, National BIM Standard, British CAD standards, Eurocode CAD standards etc. This further creates confusion amongst designers. Even though all follow similar pattern, they differ between them.

There are cases, where in large projects consultants come from around the world ( Architect from US, Interior designer from Spain, Structural Engineer from UK ), and each set of construction drawings have a different drawing numbering scheme.

After trying to review some of such CAD drawings / documents numbering standards, we are presenting here the US National CAD standard, which in my opinion is the simplest and easier to use from all the others.


As you can see from the example here, there are three (3) components to the drawing number structure.

The first two (2) letters are called the discipline designator indicating the discipline/design profession or trade.

The third (3rd) digit represents the sheet type of drawing (i.e. plan views, details, sections, schedules etc).

Finally, the last two (2) digits are basically the sequence number of drawings in the series of the same type. They can be any sequential number from 00 to 99 and the purpose is to place the drawings in order.