Exporting CAD backgrounds: Would Revit automatically adjust layers per phasing?

[mhaidar]

i created a .txt file to control the CAD background layers to be exported.
Is there a way one can make Revit differentiate between a demo element vs. a new or existing element and assign it to the adequate layer?
I noticed there is only one row per Revit category to assign a layer name to. So how can you assign 3 layers, to one category. as in the case of a wall that might belong to 3 categories

Revit Category CAD Layer Name
Wall A-Wall-N
A-Wall-E
A-Wall-D
Thanks - Mo

[DaveP]

Revit will export the AutoCAD Layers depending on which Revit View you are exporting from. What happens with the Phases is that Revit appends "-EXIST" or "-DEMO" for the phase. So, if you've got the Revit Wall category exporting to "A-WALL", you'll get
new walls on A-WALL, and
demolished walls on A-WALL-DEMO

To answer your next question; no, you can't adjust what gets appended. You're stuck with -DEMO or -EXIST

[mhaidar]

:)
Thanks for answering the next one already
Mo

[Steve_Stafford]

You can refer to this Article (http://revitoped.blogspot.com/2006/07/phased-by-your-exports.html) for a little more background since this phasing adjustment didn't used to happen automatically. I believe they've added the additional lines to the stock import/export file since though.

[mhaidar]

David
i realized you can change what gets appended in the export txt file. just type -D instead of -Demo in the demolished row and -e instead of -EXIST.

Steve
thanks for the forward. the one thing i still couldn't do is to append -N on a new construction. the only way to append the wall layers for example for new walls by -N is to assign A-Wall-N layer to the wall category.
i am working on a project for the VA in long beach and they have their own CAD standards and require that the dwgs we submit are per their layer nomenclature. the -N is to be appended to any new construction layer.the problem with that is that your demo walls will be on a layer named A-Wall-N-D

[s.kamyab]

Hello,
I have the same problem about linking revit categories to specific layers in cad. This time i want to take the structural property (Bearing , non-bearing) show up in the list so that when i export those bearing walls, they go to for example A-Wall-B or something.
I have tried adding subcategory in object style which leads to the same subcategory showing up in the Export Layers dialog box but they don't mean anything, they are not connecteto anything.