Face Based Family won't host

[norcaljess]

My face based Air Terminals will not let me place them in the current project I'm working in.  When I try to place them, I get an error that says "Couldn't find an appropriate Host.  Try selecting a different Host Face or switch Placement Mode."  I have used them in 3 other projects with no problems.  Any idea why I can't get the ceiling to host them in this one?  Would it have something to do with the way I have the View Graphics set up for the architectural background?

Thanks

Jess

[julianjameson8403]

I presume you have ceilings visible in the view and that they sit within your view range and cut plane? Are you placing in floor plan or RCP? If floor plan - try using a ceiling plan to place them

[norcaljess]

I do have ceilings visible in VG.  Already checked that.  I am placing them in an RCP view, not floor plan.  However, I did try to do it in a floor plan when it wouldn't work in the RCP.  Didn't make a difference.  I've checked my view range & cut plane as well.  I am within the correct limits.

Thanks,

Jess

[CoreyDaun]

Is it just that family that won't find a host? And in the View in which you are inserting the family, make sure that the host is visible (and isn't just a hatch pattern or something) - tab through the link elements and make sure you can see it.

[norcaljess · Accepted solution]

Just found a resolution for this problem.  Went into the Link's VG and turned off all categories under the Model Category tab EXCEPT ceilings.  This worked.  I then turned ONLY the lighting fixtures category back on so I could center my registers between them, and suddenly the ceiling won't host my registers again.  So it appears to be something with the light fixtures that the architect has in their model.  I can work with this.  I'll just place my registers, then move them after I turn the fixtures back on. 

[CoreyDaun]

The reason for this behavior is that the architect's lights are still cutting holes into their ceilings, and since there is a "hole" there, you cannot host anything to that particular spot. One of our early solutions to this was to create Generic Ceilings to host our elements.

[norcaljess]

Even though it's not just that hole, but the entire ceiling that won't host my family?  And if that's the case, then why will it host my family when I turn the lights off?

[CoreyDaun]

You're right, then. There's another issue going on there. If you end up finding out any more info, please post. I believe I have heard of this before, and I'd like to know the reasons...

[norcaljess]

Will do.

[justins]

Thanks for figuring that out, we are having the same problem.  Even tried hosting in a 3D view and had no luck.  If you figure out why this is happening please post.  I'll be looking into it to and will post if I figure anything out.

[norcaljess]

You're welcome.  I still haven't learned what the lighting families contain that prevent our air terminals from hosting to the ceiling but I've added this "isolate elements" form of trouble shooting to my list of things to check in the future when a family is acting contrary to the norm.

[CoreyDaun]

Question: After placing your hosted Air Terminals on the face of the linked ceiling, what does "Host" read under its Properties?

I cannot get a face-based fixture to host to a linked ceiling in this project, period. I can go into a Section and designate the ceiling face as the current Work Plane and then place the fixtures. And I made a fake test project with a linked ceiling, and it worked without any issues. It may have to do with the way the architect created the ceilings...

[norcaljess]

The Host in the properties reads: Linked Revit Model:... and then the name of the architectural revit model that I have linked.  So even if you go into the View Graphics of the Revit Links and make a custom view where you turn off everything but the Ceilings category, it still won't work?

[julianjameson8403]

Guys - just a thought on levels.

If you have ceilinglinked then don't you create plenum levels to create spaces? If so, can't you just change the hosting from face to hosting by plane - the plane being the relevant plenum level? Or have you guys tried that already.

Just thinking of a short term easy work around without adding additional ref planes, etc or spending ages trying to work out the illogical works of Revit/Architects.

[CoreyDaun]

Just ceilings doesn't work, either. I looked at one of the ceilings that were copied over from the Arch model and it seems to be beyond MEP's comprehension. When selected, it does not register a Type (blank in the Type Selector) and when Type Properties is selected, its devoid of everything except the typical Identity Parameters (Keynote, Model, Type Comment, etc.). Advanced RAC abilities I assume.

 julianjameson8403 - That's the way to do it, but I was just aiming to figure out one of the many, many "why's" of Revit.

Our firm copies over the ceiling so that we can manipulate the grid, so this issue is not a direct problem for us.

[julianjameson8403]

Oh the why's of Revit - one could waste their life trying to work out why things don't behave the way they should!!

Just some thoughts on possibly locating the cause:-

Have you tested different types of ceiling in the linked model - i.e checked if it is anything to do with OOTB ceilings as compared to Architect made ceilings?

What happens to the behaviour if you remove the architect's light fittings from their model? What happens if you change their fittings to something that doesn't automatically cut holes in the ceilings?

Do the combinations of ceilings and lighting fittings cause the problem - i.e does the same combo break elsewhere or is athere a specific combo that causes the problem?

I noticed that in RAC 2012 the light fittings automatically cut holes in ceilings irrespective of the check box in the family categories. Not sure if that happened in 2011 as not an Architect (fortunately) but wonder if that functionality is now causeing this problem for certain types of ceilings?

Not sure how many of these you have looked at or mentioned previously but just putting them out there as ideas.

[AFL22]

In case anybody is still interested. What I did is cut a section to the area where I was having a problem hosting a ceiling based air terminals. I created a 3D view and oriented the view to the section. Then I hosted the air terminal to the face of the ceiling. Walla it hosted.