We need the ability to control what material is applied to an element respective to project phases. For example, we need to show that the paint in the Dining Room is "cream" in the Existing Phase, while the paint in the Dining Room is "blue" in the New Construction phase. The wall isn't being demolished, just painted, and currently there is no way to do this in Revit. Our clients are increasingly wanting us to use the 3D model and renderings to visualize existing vs new materials.
Once workaround is to model the finish layers and core layers in the wall as a separate walls. However, this is incredibly tedious and still causes problems with the demo plans. This workaround also doesn't work for stairs. If I need to change the material on a stair from one phase to another, I have to demolish the entire staircase! BAH!
I see this feature being working in three possible ways:
1. Let the "Paint (PT)" tool remember what phase an element was painted in and then show correctly in each phase. This isn't ideal because not everything can be "painted" and having to custom paint all the surfaces in a building is already tedious and a waste of time, but it seems to me it is the quickest way to implement the feature.
2. Make the "Material" type parameter a dual-entry parameter so we can select the "Phase" before we select the "Material". This seems difficult to implement because it doesn't seem Revit's parameter types are structured to be able to accept two entries for one parameter.
3. IDEAL SOLUTION: Update the "Appearance" tab in the Material Browser that will let us assign a different "Appearance Asset" to each phase for that material. Each material's appearance asset is applied to the first phase in the project by default and all the following phases inherit the most recent asset applied.
I think solution #3 is the best for the user experience. For example, I can create a "Dining Room Paint" material that has an appearance asset that represents the existing conditions and is applied to all the dining room walls' finish layer. Within the Material Browser I can then got to the Appearance tab, select the "New Construction" phase and then change the appearance asset for that phase. Then when I render both the existing conditions and the new conditions then the paint colors are accurate for the phasing and I didn't have to fake demo anything to make it happen. This method would work for everything in Revit including walls, floors, roofs, stairs, ceilings, and even families that use materials!