Diffusers on the move...

[Anonymous]

Revit MEP 2009, we are experiencing a problem with our face-based ceiling
diffuser moving when we receive an updated architectural model that is
linked into our model.

We know if the architect "deletes" their ceiling and recreates it, we need
to realign the diffusers and rehost to the ceiling. I understand why they
need to be rehosted, but I wish they would not change their origin, but they
do. We have seen diffusers move completely outside the room!

In some situations, the architect "modifies" their ceiling and when we open
our model with the new architect's model our diffusers moves an inch or two
off the ceiling grid from where it was originally located. They still remain
hosted to the ceiling level. Our first thought was the ceiling grid moved or
changed. However when we went into the old model and measured the diffuser
location and did the same thing in the revised model, the diffuser moved -
not the ceiling grid.

We have experienced this several times with different models. Though this is
a small project, I see a huge problem in dealing with a large project with
hundreds (or thousands) of diffusers. Is anyone else experiencing this
behavior?

I'm thinking about placing reference planes at the various ceiling height
and use the reference plane for locating our diffusers rather than relying
on the linked ceiling plan. Any suggestions?


Thanks,

Dennis

[simon.whitbread]

You have two options here Dennis,

1. Don't use 'hosted elements' - Lights, Diffusers etc then have an offset from the level. Yes, you would have to coordinate with the ceiling heights, but they won't move or disappear.
2. Create your own ceilings (even if the material is 100% transparent) and host your objects to those

Reference planes - Don't
1. You have to rely on the user KNOWING which way they have been created (left to right - AND in which view)
2. They look messy (I don't like mess!)
3. IMO they make things more complex. I guess if you are the only one using Revit it doesn't matter, but if you share your model back to other companies - you won't get much thanks, its like a badly constructed Architects file.

hth

Simon

[mojova]

If we were to create our own ceiling plan is there a way to link it somewhat to the architectural ceiling in order to avoid missing a ceiling update where the ceiling moved up 4"? I'm starting to wonder why hosting is even an option...

Is there a way to host to a linked file for the initial placement and then break that association intentionally so that things don't go haywire when the arch moves/deletes/changes whatever you might have been linking to?

Thanks,
Mike

[simon.whitbread]

Unfortunately - or fortunately, depending on your outlook - you cannot do this, you have to rely on the architect telling you, or you actually checking.

You could 'bind' the Architectural file, which would turn the architecture into a 'group' - not ideal, as Architects files can be large.

One thing you could do, is ask the Architect to supply their ceilings as a group (which is really a Revit project file), and to maintain that group in their project.
Each time they issue you their model, you get an updated 'ceiling group.rvt' which could override the ceiling group in your project. A bit of management, you would need to turn off linked ceilings, but thats a cleanup method similar to that described in my blog...

http://bim-bs.blogspot.com/2008/12/linked-file-cleanup.html

Also talk to the architect and ask them not to delete things that already exist - CHANGE is good, Revit is the Change engine

Simon