Revit has some fantastic "Phasing" features that can simplify working in renovation projects and other projects that have multiple demolition and/or construction phases. Today I came across a request that surprisingly enough, I have never heard before. ACT Ceilings in Revit will demo but the fill pattern that they use is not overridden like model elements are. When a ceiling is demo'd in Revit, the ceiling pattern stays the same(non-dashed) and so the request that was made was for an ACT ceiling pattern that represented itself as demo'd (dashed).
Ceiling patterns in Revit are fairly straight forward and follow simple rules. You can make your own with a text file. I created two "Demo" ceiling patterns and have placed them in our Revit Standards Library. If you are interested in making your own patterns, take a look at this blog post on iRevit.com.
If you need the 2x4 or 2x2 demo ceiling pattern, there they are.