Revit has Two types of Fill Patterns: Drafting & Model. Like AutoCAD, Revit too has same method of Definition to create Patterns, hence the Revit Fill Patterns can be found in Program files/Autodesk/ Revit Architecture 2014/ Data.. which has both Metric & Imperial Revit.Pat files.

If we want a Model Pattern to be available as Drafting Pattern, typically in some cases like CutPattern does not allow model patterns, its disabled as shown below: Then follow this procedure to create a new Drafting Pattern that has the same fill pattern as the Model one.
In this Example I will take Brick Pattern available in Model but not as Drafting.
1. Open the Revit.Pat file or Revit Metric.Pat file based on the units you are working.
2. Search for the Pattern name ..here Brick, Copy the Definition completely & paste to a new notepad file
3. Change ;%TYPE=MODEL TO ;%TYPE=DRAFTING
4. Save the file as giving the same name as that of the pattern here.. Brick.Pat under types of file set as All Files
5. Now open Revit … Manage… Additional Settings….Fill pattern…Select Drafting pattern….New…..choose custom…import….select the Brick.Pat file….set the import scale till you see a preview correctly…once imported this cannot be changed, you can only re import & change.

6. This will henceforth be a drafting pattern that can be selected as cutpattern in material Library.
Note: Type=Model or Drafting in the definition defines the type of Pattern.
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