Aligning base point, coordinates with Linked ARCH - Best practices.

[jwinklerSB4SV]

I am beginning to understand the Revit's complex 3 part coordinate system due to some helpful online tutorials.  The problem is - most of the tutorials, and even Autodesk instruction are from the architect's point of view.  As an MEP Engineer, we typically coordinate the Base Point, Origin, and Survey point when we receive the Architect's first model.  We acquire shared coordinates, and set the project base point and orientation to match the Architect.

However, as most architects know - at some point in the project, the architect will update the project position -well into the project -as the Civil Engineering info is received.  This leaves our MEP model with differing survey point, and origin.  I have heard it is dangerous to unclip the survey point.  What is the best workflow to change the MEP project positioning once the project is well underway, without moving and rotating every item in our model (very time consuming and dangerous)?

[mhand52 · Accepted solution]

We have encountered a similar issue at my firm where we are a full-service company and have in-house Architects working with our engineers. We created a bit of a workaround process because this is something that is inevitable regardless of working with our in-house Archs or external consultants.

What we did was create a "Master Site Model" that has all of the different discipline's model linked into it. Starting with the Arch model, this is moved into the correct location as pertains to the Civil background, and then we "Publish Coordinates" to that Arch model. We then do the same to each of the consultants models using a common grid intersection for the building to make the move/rotate simple. Within each consultant's model itself, the models are all technically still located around their native (0,0,0) location and can be linked with standard origin-to-origin. But because we published coordinates to each of those models, when linked into a fresh project by Shared Coordinates, they will all be located correctly relative to each other. 

This is nice because, as the building location/rotation does inevitably change over time, you can just move the whole group of models in the Master Site file, re-publish coordinates, and they are all satisfied again.

I will note, this workflow isn't super straight forward, and staff are prone to miss steps, but it does beat chasing down a moving background. It will take some practice, but it has proven itself when followed correctly.