change demolition phase for families that are part of a group

[HVAC-Novice]

I have a lighting project with light fixtures within cabinets. there are multiple cabinets of the same type and i created a group that includes the cabinets and the light fixture in the cabinet. i placed them in existing phase. The reason i used groups is, to place the fixture family in the cabinet i need to use a 3D view (it is a type of in-cabinet desk) and I wanted to save some time. 

In the new phase i want to keep the cabinet as NOT demolished. But the light fixtures should be demolished. 

I edited the group and set the light fixture as demolished. But that doesn't seem to propagate to the other instances. when i select all fixtures in the view (to set them all to demolished), this only works for light fixtures that aren't part of a group. 

The only way I can change those light fixtures to demolished, is to hover over each group instance and tab to select the light fixture, and then set it to demolished in new phase. 

I haven't really used groups before. But it seems they can't deal with phases/demolition. And items in a group can't really be selected with a simple (select by dragging mouse and filtering).

Well, it is done now. But I wonder if there would have been a better way to do this? Or if there is an easier way to selectively demolish items in a group. 

Edit: One trick is to ungroup the groups. that way the light fixture can be selected along with the other "normal" fixtures. Obviously that would prevent me from doing any group-editing and I have to be sure those elements don't need editing anymore.

[lucdoucet_msdl]

---

@HVAC-Novice wrote:

I edited the group and set the light fixture as demolished. But that doesn't seem to propagate to the other instances. when i select all fixtures in the view (to set them all to demolished), this only works for light fixtures that aren't part of a group. 

Yes unfortunately group members inherit the phase of the view in which the group was placed and then retain only individually assigned (or instance) creation and demolition phases. So, no; changing the phase settings in the group edit mode won't propagate to all instances of the group.

---

The only way I can change those light fixtures to demolished, is to hover over each group instance and tab to select the light fixture, and then set it to demolished in new phase. 

An alternative to manually changing in a 3D or 2D view would be to create a light nomenclature with the type and creation/demolition phase parameters. Filter to only the light fixtures you want and you can click down the list to change the phase parameters more quickly than in the view. This will change the setting even if the light fixtures are in a group.

---

Well, it is done now. But I wonder if there would have been a better way to do this? Or if there is an easier way to selectively demolish items in a group. 

An alternative solution would be to convert the groups to Revit linked files if the need change the phase of group elements needs to evolve with the design process (ex. the light fixture needs to be reset to be maintenained for budgetary reasons!). You would then have the phases mapped between the main project and the multiple linked projects containing the cabinets and lighting.

A more practical example would be in choosing the group versus Revit link phased work in identical spaces (office or multi-residential units).

To replace all groups with a Revit project file : See this Revit help page:

Convert Groups to Linked Models

---

Edit: One trick is to ungroup the groups. that way the light fixture can be selected along with the other "normal" fixtures. Obviously that would prevent me from doing any group-editing and I have to be sure those elements don't need editing anymore.

---

Rather than ungrouping, you may rather want to keep the groups and remove the light fixture as a member of the group. When "removed" during a group edit, the light fixtures are kept in the model and "seperated" from the group. This is as opposed to deleting the light fixture while in group editing mode which removes it from the group but also all instances of the group in the project. By "removing", you can then proceed to phase the light fixtures on a individual basis.

Hope this helps,

-luc

P.S. Groups in Revit have many idiosyncrasies. I would suggest you read up on best practices when deciding whether to use model groups or alternative methodes of repeating like items. Here is a nice summary of best practices:

https://www.quadmeta.com/blog/revit-group-best-practices-a-guide-for-efficient-bim-modelling

[lucdoucet_msdl]

@HVAC-Novice 

I've created the attached dynamo script as proof of concept to update all instances of a selected group changing their wall elements from existing to demolished.

This script could be adapted to your use case by replacing the wall category by light fixture so long as all the light fixtures in your group are to be demolished. It would require some more work to selectively demolish a light fixture type leaving other fixtures as is.

This method works based on the idea that Revit groups are instances and dynamo can collect their contents quite easily as opposed to effecting changes in Revit families.

Hope this helps,

-luc

P.S. Attached dynamo script may contain specialty nodes from packages online.