Monday, January 14, 2019

Managing Opening Infills for Doors and Windows

I recently wrote a post about the challenges representing demo'ed openings in an existing floor element in Autodesk Revit; Revit Challenge: Demo Hole in Existing Floor.


As a follow up to that, this article was inspired by my friend Pieter Schiettecatte, who wrote:
"Related to this theme: if you’re ever thinking of doing an article on infills, I have a great suggestion for those 😊 
There’s a popular Revit Idea to make them ‘optional’, but I would vote for getting rid of them completely. 
  1. The infill is a confusing feature for a lot of users
  2. Even in the case we want to infill the resulting opening, it is almost never with the same wall type as the original wall so the automatic infill is useless for that
  3. So as far as I’m concerned, the only use for it is to be able to host a new window in the opening of where an old window used to be.
A much cleaner workflow would be: get rid of infill elements completely and enable us to host elements in openings in the host. So we could pop in a new door in the entire ‘extent’ of the wall, which includes its openings. This would also reduce the ‘element has lost host’ errors." 
Here is an overview on how automatic infills work within a demo'ed opening...

The following image shows various combinations of a door in a wall - windows work the same way. The penultimate row shows the infill elements in the demo'ed openings. The last row shows those same infills removed using a view filter.


When a door is demo'ed, Revit automatically fills the opening with the same wall type as the host wall. In theory that makes since. If you are removing an opening you would use the same construction to fill the hole. However, in reality there are many things wrong with that assumption. Like, what if we just want an opening in the wall, or the wall is a 100 years old and the same, exact, materials are no longer available or practical, etc.

In the case that you want the demo'ed opening to just be an opening, not infilled with anything, one technique to remove the infill is to use a View Filter. In this case I manually enter "void" in the Comments instance parameter as shown below. You would not want to use a Type Parameter as you might want some infills to remain, and that would apply to all walls, not just infills.


Once the infill has been made unique via the Comments parameter, we can create a Filter based on Walls (category) and the Comments (parameter) being equal to "void" as shown here.


Next, you apply that Filter to a View Filter, better a View Template, and then set it to not be visible when that filter's criteria is met in the given view.


Now the infills are hidden in the given view... but, only the given view. The rouge wall(s) - i.e. infill - can still show up in sections, elevations, 3d views and schedules. You can catch a lot of these by widely using View Templates (highly recommended, in general) but then there are the other disciplines who would need to take similar action. So the chances of an infill showing up when it should not are pretty good on the average project.

It should also be pointed out that infills cannot be deleted... you get the warning shown here when you try.

The infill can be selected and swapped out with another available wall type.


And, something I did not know until writing this post, the infill can be aligned with the face of the host wall. In the next image I changed the thickness of the existing wall and the infill stayed aligned with the face of the host. Other than that, the ability to reposition the infill within the host is very limiting.


Here is a short video I just posted on YouTube showing how I repositioned the infill wall. Still limiting, but may help in some cases.


Please share your thoughts and challenges on this subject in the comments below!

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