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Al Whitley/3 min read

Understanding Detail Numbering in Construction Documents

Detail Reference System

Detail Bubble

Top number = detail number, bottom number = sheet where detail lives.

Cross-Referencing

Plan view points to a detail; the detail sheet shows the zoomed-in section.

Sheet Numbering

A-series = architectural, S = structural, M = mechanical, etc.

Revisions

Cloud + revision triangle marks updates between drawing issues.

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This tutorial walks through understanding detail numbering in construction documents, covering essential tools and techniques for your projects.

Well, I might be getting a little bit ahead of myself, but we've just finished completing the detail borders, and I wanted to show you how we tend to use details on a sheet. Now, I have information about 22x34 and 30x42 sheets. I think everyone knows that typically when you assemble a set of construction documents, that they are stapled on the left side.

So, when we work with construction documents, we tend to flip from the right side of the page to the left. And for that reason, when we number the details, we typically start 1,2, 3,4, 5,6, 7,8, and so on and so forth. So, the detail numbers go down, and they go to the left.

Typically, if we happen to have different sized detail borders, the detail numbers tend to correspond to their standard position should there be different formats. So, you can see this detail is 1,2, 4,6, 8,9, 11,13, and 16. So, again, if it were just a 1x1, it would be a 13.

Typically, the bottom right area of a detail determines the detail number. And this tends to happen whether you're on a 22x34 or a 30x42. This is not an industry requirement.

It's an industry standard. But, again, you can see number 6 here, bottom position corresponds to 6 here, 7 here, and 7 here. Now, it might very well be that this vertical detail in a 22x34 project is the same as this detail on a 30x42 project.

And this is one of the reasons why we do not include the detail numbers in the detail file itself, because if all of the contents of the detail are identical, if I were to include the detail number in the detail itself, I'd have to take this detail, copy it, and then rename it to go over to here. But by keeping the detail numbers out of the detail itself, we can have a company library of details and then position them within the set according to the best way that typically the project Architect, project engineer, or sometimes the contractor deems necessary. So I hope that this has helped you understand a little bit more about detail numbering, why we do not include the detail numbers within the details themselves, and that you are beginning to understand the most effective way of working with details and assembling details within a set of construction documents.