By Jordan Mussett, IMAGINiT Building Solutions
Deliverables for projects utilizing Revit often include dwg copies of the drawings in addition to the pdfs and native Revit files. That is normal, but sometimes the client has their own CAD standards that you have to comply with for that deliverable. This post will explain how to override necessary layers in the export dialogue so you don’t have to get into scripting a bunch of AutoCAD dwgs unnecessarily.
Let’s start with the high level options. You have a default layer export that is chosen for you based on the AIA layer guidelines. There are several others, but for architecture, the AIA is the best place to start. Once you get to the next dialogue box, you can choose to name the file manually or have the computer generate a name based on the project name and the view name, choose the AutoCAD year format, and whether you would like to export your Revit links as xrefs. The last option is the most important in here for me. If you uncheck this box, it is kind of like binding all layers together in one file.
For this post, I will be leaving these save settings static as shown below for the behavior that I really want to point out which comes from changing settings in the Export Setup.
You can customize just about all of the AutoCAD Layers that get exported to AutoCAD, which is a good thing. The trouble is, you are not always able to override everything that is in another Revit Link when exporting to AutoCAD – or so I thought.
Now let’s visit the override dialogue box. I am going to change the cut layer name and color of the wall pattern. I changed the initial setting from “A-WALL-PATT” to “A-WALL-PATT-IMAGINiT” Color ID 6 (magenta). An important thing to remember is that the wall on the left in this section export is in the Architectural Revit file, the wall on the right is in the MEP file. I will be exporting the sections to dwg from the MEP file. As you can see, there are quite a few line items and quite a few tabs. For this example, I am only going to change the one item circled below.
The other variable at play here is the Export layer options. From now on, I will refer to these as Export layer options A, B, and C.
Here is the same screenshot in AutoCAD from the three different options. Remember, the wall on the right, I drew in the MEP Revit file to show more clearly some of these export behaviors.
With Option A – the override didn’t make it through to the wall in the linked file on the left. The cut pattern of the wall is still yellow.
With Option B, the override does make it into the walls that are in the linked Architectural Revit model.
Option C applies the override to the wall within the MEP file and creates additional layers. Oddly enough, there is no linework on “A-WALL-PATT-IMAGINiT”.
As a recap, if you need to override and export to meet client demands, you probably want to uncheck create xrefs in the save options (so you don’t have to bind them afterward), and choose option B for the Export Layer options so overrides can permeate objects in the Revit links.