Phases are a pretty difficult animal in Revit to wrap your head around.  The reason it is difficult is that the functionality works a little differently that is expected.   Architects have very specific uses for Phases while designing and working on a project.  Revit doesn’t always mesh with those uses exactly.

The most common problem with phasing is that users can’t get objects to display the way they would like to in a view.  This problem actually contains 5 different parts.  View properties, Phases, Phase filters, Graphic Overrides, and finally the properties for a object.  In order for the objects to display correctly all of these things must be setup correctly.  If any one thing is not correct, the objects in the phase will not look correct.  Three of these items are all controlled in the Phasing dialog box so let’s take a look at that first.

Above is the Phase Dialog showing the Project Phases tab.  The important thing to note here is that there are the words FUTURE and PAST in this dialog and your projects phases are in-between.  This is a time line of your project and where each phase is placed determines how it displays in relation to the phases around it. 

There is not an indication of what the current phase of the project is.  This is something that is set in the View properties, as each view can have a different phase set as the phase for that view.  A common mistake with Project Phases is that users create a Demolition phase.  Demolish is actually already defined in Revit as a Phase Status and creating a project phase for just demolition is a very frequent offender of display problems.  This is where Revit doesn’t exactly work like an Architect thinks.  

It’s pretty common to say for an Architect that there is a phase where all the demolition occurs before you actually start any new construction.  However, Revit sees demolished objects differently.  It sees demolished objects as a state of being for the object and not a phase of the project.  Revit does this so that a object that is demolished during construction can also be shown as a existing object at certain points in the project (like when showing existing conditions). 

I am going to flip over to the Graphics override tab which should help to explain this further.

This dialog tells you the four statuses that any object in Revit can have at any time.  These are the only phase statuses that are available; unfortunately, you cannot add your own to the list.   The phase status of an object is determined by which phase the view is set to display in view Properties.  If your view is set to the phase of Existing, any object that was created in the Existing phase (has a property saying it was created in Existing) will display as having a phase status of New.  This can be a little tricky to wrap your head around because in Revit we name our Project Phases very similar to the Phase Statuses.

Instead of naming your Project Phases: Existing, New Construction, etc, try naming them: Phase 1, Phase 2, etc.  This makes understanding the statuses of an object easier.  Here’s a list to show you how Revit determines the Phases Status of an object.  This is right out of the Revit help file…

• New: Element was created in the phase of the current view.
• Existing: Element was created in an earlier phase and continues to exist in the current phase.
• Demolished: Element was created in an earlier phase and demolished in the current phase.
• Temporary: Element was created and demolished during the current phase.

It’s important to note that you do not have a Future phase status.  This means that you cannot display items in Revit that appear in a future phase.  You only have the ability to show what was and is done up to and including the phase that is set in the view properties of the view.   You can work-around this problem if you need to, but it can require changing all your graphic overrides and it might be easier just to draw the objects you need to future in the phase for that view and then manually override the display of the objects that are future.

Phase filters allow you to control how each of the above Phase Statuses display in a view.  For each phase status you only have three choices for each filter. 

• By Category - The display settings in Visibility and graphics for that view will be used to display any objects in that Phase Status. 
• Not Displayed –Any object that is that Phase Status will not display in the view
• Overridden – Any object that is that Phase Status will use the Graphic override that is set on the Graphic Overrides tab of the Phases dialog.  

With phase filters you can create as many filters as you want by adding new filters if needed or you can delete them as needed.   One thing to note about Phase Filters is that for Overridden objects, you only have one choice of the overrides used. 

All Phase filters have to use the same set of overrides on the graphics override tab and different phase filters can’t have different overrides.  Sometimes is necessary to use a filter that is set to By Category but use visibility and graphics to change the display of the objects of that Status to get the look you would like for your view.

The last two things to look at are view properties and object properties. 

View properties have a Phasing section that controls the phase for the view, and the phase filter that is being applied.  These two are taken right from the Phases dialog box. 

Almost every element or object in Revit has Phasing properties as well.  There are two properties here, Phase Created and Phase Demolished. This is exactly how it looks.  The phase that the object was created in and if the object was demolished, the phase it was demolished.  These two properties along with the Phase property for the view determine the Phase status for the object. 

In closing, phasing is a very powerful tool once you understand how it all functions work together.   It can take a little experimentation to get the display you would like, but just about any look is possible with the phasing.  

I know that this is along post, but hopefully, it has given you a little insight into phasing, how to works, and how you can use it.