Mirroring elements

[eriktoom]

Hey, 

I am doing an electrical project and the apartment building has identical apartments on the other side of the house. I am working in a linked model and whenever I mirror the elements (with dimensions and tags) Revit gives a message Can't mirror element into this position. The only way to proceed is either click Delete elements or Cancel. I couldn't find any forum post on this. Any ideas? 

[iainsavage]

I’ve never really had problems mirroring elements like this - can I suggest that you upload the model for examination?

[sragan]

If elements are "hosted" to walls or other elements from a linked model, they won't just automatically find a new wall to host to when they are mirrored.  

In that case, you will probably just have to recreate all the elements again. 

Sucks, but that's the way Revit works.

[iainsavage]

That isn’t strictly true. - Revit will try to find a suitable host and will allow elements to be mirrored or copied if a suitable host exists. If a host doesn’t exist it will usually give a warning that “Element will lose association to host” but still allow the mirror/copy to occur.

In @eriktoom case, if both halves of the building are identical but opposite handed and if the mirror axis is exactly in the middle then the mirroring should work fine.

I suspect this is a different issue, possibly something to do with one of the families.

The best way to get a solution is to upload the model and let people examine it.

[s.borello]

Did you try grouping the objects, then mirror?

[Mahmoud.Ziedan]

@eriktoom 

We used to face a lot of problems with hosted families especially with previous Revit versions.I believe when the walls are not equally mirrored,this will occur.
there are some turn around but usually I prefer to use non-hosted families.

[iainsavage]

Below I have mirrored face hosted families using the wall centreline. The sensors on the wall face have found a suitable host when mirrored, the air terminals have not found the ceiling as a host but have still placed. 

In this next example I have mirrored over a random axis line - all become unhosted but still place.

In this example the mirror axis is at 45 degrees - same result as previous.

In none of these cases did the mirror fail completely or the error message experienced by @eriktoom appear.

I've only ever had that error once with a particular manufacturer's plumbing fixture family.

So I don't think its as simple as saying that hosted families are a problem or that Revit sucks, I think there is more to this and at the risk of being boring and repetitive @eriktoom should upload the project file so that people can investigate it rather than guessing.

[eriktoom]

I can not upload that massive project unfortunately. It works only when grouping the models, then selecting the grouped models with its tags and dimensions and then mirroring. I need to see if I have the same issue on any test-project.

[RobDraw]

It's not necessary to upload a huge model.  A small portion that exhibits the issue is very helpful in making sure everyone is on the same page. It makes it easier to get the help you need and eliminates any guesswork. 

[gary.cowan]

FYI if any of your electrical families have symbols within them the symbol will also be mirrored, and will not correspond to any symbol legends you may use.

same with any writing on the family. it will be back to front.

also if any of the models are anything like a MVHR unit with specific outlet arrangements, it will mirror and not be representative of the actual family.

mirroring is not a great idea for families, ok for walls etc, not so good for families best to avoid.