I written before that I occasionally experience something that feels like a "Revitary alignment" regarding features in Revit. I'll see a post at AUGI or get an email or two from friends or clients asking about the same thing or theme. I recently ran into a user that manipulated their project by moving the Project Base Point. Then a post at AUGi meandered into a related conversation.

General Statements

  • The Survey Point allows us to show where an imported CAD file's origin is relative to your model (CLIPPED)
  • The Survey Point allows us to identify a benchmark location on the site instead or referencing source file's origin (UNCLIPPED)
  • The Project Base Point does not ever "need" to be moved (CLIPPED) normally (my opinion/belief/preference)
  • The Project Base Point will allow us to move our project on the site to reposition it (CLIPPED) but the file origin isn't changed
  • The Project Base Point (UNCLIPPED) will let us identify an alternate location that Spot Elevations and Spot Coordinates can reference

Applied to a Project

Let's say you design a house, import a survey and it's off to the right and above your building. If you use Acquire Coordinates on the survey file you should find the Survey Point (CLIPPED) moves to mark the origin of the source survey data file (sometimes this is quite far away). The Project Base Point (CLIPPED) can be used to reposition the building over the site. Just drag or move it with specific values. What you see moving is the "Project". The file origin is untouched and you should see that the linked survey file isn't moving either. If you import a small origin "marker" file using Auto - Origin to Origin you'll find that it lands at the Project Base Point. Now if you move the Project Base Point (UNCLIPPED) you see that you can move the icon to another location but it still references the "file origin" (see image).

That approach works for a single building on site but is not very effective for multiple buildings on site. The approach I advocate where we create a site file that is coordinated with survey data and serves as the master coordinator for multiple buildings which are linked into this master site file is much more effective and versatile. Since this subject can be confusing enough I advocate using the same approach for any project so I can learn one technique and use it over and over, since it works for any project.

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