Ceiling lights not cutting host?

[krscad]

Has anyone ever had this problem? 

I am working on a large hospitality project and have been having issues with ceiling hosted lights. I have a group instance representing a unit type, and was trying to place a couple recessed can lights. The ceiling is part of the group. The phases are all the same. The light will place, but when I try to exit the group editor, I get an error that reads "cannot cut instance from host" and I can either choose to delete my lights or can not exit the group editor. 

I tried using lights that did not cut the ceiling. In these instances, upon exiting the group editor, I would get an error stating my lights had been moved to project to avoid inconsistencies. There is only one instance of my group. 

After searching forums and finding nothing specifically relevant, I noticed a post about lights working on one ceiling type and not another. So I tried it, and it works. The lights will host on one ceiling type, but not another. I checked every parameter within the ceiling types and materials, even going so far as to duplicate the types and materials and narrowed it down to difference. 

The lights work if the ceiling has a surface hatch pattern, and they do not work if it has no hatch pattern. We were using hatch/no hatch in our RCP legend to show where the soffits were, so I created a solid white hatch pattern, and it worked. 

To make things more confusing, I have another group, representing another unit type, which I created yesterday, and in that group, the recessed lights worked just fine. 

[ToanDN]

Is the ceiling in the troubling group also having some hatch pattern assigned?

[krscad]

The ceiling only causes problems when there is no surface hatch pattern assigned. Assign a pattern, any pattern, and the lights host properly. 

[BalajiHTI]

Dear krscad,

Can you attach the lighting fixture family and simple project file with two cases you mentioned about ceiling being cut and not?

Because, I want to take a look at the situation to help you better.

Thanks!

[krscad]

I tried creating a new simple project file to attach but was unable to duplicate the problem. The can light is just the default family "Downlight - Recessed Can" that is included with Revit. The ceiling was part of our template, but in the course of troubleshooting I also tried using the Revit default material "Gypsum Wall Board," and got the same result. With recessed lights I get "Can't cut instance(s) of 6" Incandescent - 120V out of its host," and with surface lights I get "Group members had to be "moved to the project" (removed from their group instance) because they were not consistent with the group type definition."

I have noticed a new problem as well. Our project is a remodel, and the ceiling is existing, but if I try to create a can light in group editor mode in the "new" phase, I get an error "Curtain grid based elements cannot be grouped." If I create the light in "existing" phase I get no error, but then is there no way to add new recessed lights to an existing ceiling in a group?

[davidlogan87]

Hi,

Did you ever get a solution to this question. I have the same situatuion. Existing ceiling, existing lights removed in Demo and new lights added to same location in proposed, but the lights dont cut-out the ceiling. I can manually hide the tile element in each view but this isnt really ideal.

is there something bacis i am overlooking.

Thanks

David.

[hmunsell]

What I have done is create a Detail Item family that I place in the Light fixture family. In the detail item family I have symbolic lines, 2 filled regions (for the emergency fill) and a masking region (for non-emergency). I set 2 new parameters for Emergency and Non-Emergency so they can be turned on or off as needed when the family is placed.

It doesn't seem to mask the ceiling grids in the electrical file (not sure why), but my electrical guys only use the grid for placement and then turn it off anyway. When the Electrical model is linked into the Arch file though, the Elec lights do hide the ceiling grid in the Arch file.

I have attached a sample Recessed Light Fixture and the detail item family for your use.

[MercuryTheater]

I know this is an old post, but many people seem to have this problem.  Luckily there's an easy solution.  So if you're an engineer, then most of your families are face based.  But in a face hosted template you'll notice that the Opening tool is not an available option.  So if you want the light to automatically cut a ceiling, then do this:

- Go into a Reference Level view

- Set the work plane to the Reference Level

- Create a Void Extrusion that goes down into the face host.  Align and lock any drafting lines as needed.

- Then use the Cut tool.  Select the face host, then select the void.  The Void then cuts the face which is what Revit needs in order to automatically cut ceilings in your project.  

If you've already created a family and its not cutting the ceiling, then follow the same steps above, BUT to make your life easier, create an Extrusion (not a void extrusion).  Then select the extrusion and in the instance properties under the Identity Data group, you'll see a Solid/Void parameter.  Just change that to Void.  The prevents your void from cutting all your existing geometry.  Now use the cut tool to cut the void from the face host. 

[jwRN244]

This extrusion / void also need to be created on the correct reference plane. The same one as the host