09 Feb

(API) Left / Right door custom updater in Revit

Having multiple instances of a door or a window often carries a problem that some of them are (intentionally or not) flipped (mirrored). Flipping doors and windows is neat option but it can bring big problems. Left doors and not equal to right doors (the same goes with windows) but Revit will treat them as they are the same (if they are of the same type). The Revit Add-in I created solves this problem by updating parameter value whenever door (or window) instance is changed (flipped or mirrored) from right to left or vice versa.

I was inspired by this article, please make sure to read it first to understand what this is all about:


As I suggested in the comments section below the article, the solution to the problem is quite trivial with a little help of Revit API.

In general, I created simple application add-in which attaches custom updater to check all of the doors and windows in a project to determine if they are flipped (mirrored) or not.

The state (flipped or not) is recorded to Yes/No parameter I called (hard-coded it) “ElementFlippedOrMirrored” (it must be called that in order to get it work).

Update, May 2019: The state (flipped or not) is recorded to AREA parameter I called (hard-coded it) “ElementFlippedOrMirrored” (it must be called that in order to get it work). If area=0 the element is not flipped, if area > 0 the element is flipped. The reason why I used AREA parameter is because you can set it to be different across group instances AND can be used in formulas (very important!), so please make sure to choose this option while adding the parameter (I marked in yellow all the important settings):


I used Project Parameter for testing purposes but I strongly recommend that you use Shared Parameter since it enables using it in both: families and project.


Example on how to use it in formula, for example in schedule or in family (when using as shared parameter of AREA type called ElementFlippedOrMirrored):


Feel free to download the add-in. It should work on version Revit 2015 and above. Your feedback is welcome!

  1. Download the addin
  2. Extract all to %appdata%\Autodesk\Revit\Addins\2019   (for example, on my computer is:  C:\Users\mirko\AppData\Roaming\Autodesk\Revit\Addins\2019 ) – Revit version number may be different on your computer
  3. See video below for further instructions

Please note that you can also manually update your elements by selecting Add-Ins > External Tools dropdown > Engipedia Flipped / Mirrored command on the ribbon.

Download the add-in from Warehouse

See video below for demonstration on how add-in works (adding filter is just to show (visually) which doors are flipped and which are not. Changing (flipping) doors will update the parameter value, hence filter will color them differently.

DISCLAIMER: The software add-in is safe and made with best intentions and without any warranty. Author tested the add-in on his system but there are no guaranties it will work on your system, nor can be responsible for potential damage. Please test the add-in on non-critical project first.
If needed, you can always delete the pluging from %appdata%\Autodesk\Revit\Addins\**your revit version number** folder(s).

After you run your project, make sure that you always run updater manually before creating schedules, tags etc. You will find it under Add-Ins > External Tools dropdown > Engipedia Flipped / Mirrored command on the ribbon.


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