Xrev API Tools: Increase Productivity!



Thursday, December 06, 2007

In Place families when should I use these?

In place families trip up a lot of new revit users. Sometimes its just so quick & easy to create a family on the fly in the project.

Unfortunately though they have some real negatives. For instance they typical have a big hit on your file size especially when you start making them reference surrounding geometry in the project. Also, one of the worst things you can do in Revit is start copying around the in-place families in the project...

Many new users don't realise that unlike a normal family all the copies are actually completely new families. That is, changing one, will NOT update all the others. If it repeats it needs to be an external family.

So what in-place families do I create?

Generally the only things I'll model in place occassionally are floors, stairs & ramps. Modelling monolithic stairs and ramps as floors is a great idea as you can then attach walls to them and get those connections to floors correct. This is also because of the current limitations of the stairs & ramps.

I prefer to model complex floors as in-place purely because they don't adjust when you move walls, causing sketches to occassionaly become invalid and delete your floor. This also gives you absolute control over footings, and various beams through the slab.

Another trick is with High-Rise buildings where you have complex floors that are typical over a number of levels.
  1. I'll model the first one in-place,
  2. Then whilst still in edit family mode, copy all the geometry and paste aligned into a new external generic model family and save it as say "Floors 3-9".
  3. I then switch back to the project and delete the inplace family i just made.
  4. I create a new in-place Floor family called "Level 3 Floor" and load the generic model family "Floors 3-9" into it and place it on level 3.
  5. Then finish the family.
  6. Revit then understands that this family is a floor allowing you to attach walls to it.
  7. You can then copy and paste by level to levels 4-9 and rename in the inplace families as per the level they are apply to. Yes we did just copy and inplace family, but because its contents is purely an external family there is no real overhead in doing this. Plus if we make a change to that generic model and reload it, it will update all of our floors!
Let me know if you'd like me to post any other examples...

Revit Referencing Sheets on View Tags

Do you use the Referencing Sheets parameter in your view tags?

If you do then I bet you've had times when you thought why on earth is Revit choosing to reference from some bizarre view instead of the one you want.

Well its really quite simple -

It uses the drawing sheet numbers to determine which view to back reference.

For instance, lets say you have a sheet set as per the following:

010 Site Plan
020 Existing Plan
030 Demolition Plan
040 General Arrangement Plan
050 Elevations
060 Sections


Now lets say you have your section and elevation markers turned on in all those views and they haven't had the "hide at scales coarser than" parameter assigned properly.

In this case your Elevations & sections would display their referencing sheet as 010. This is because when you are looking through the set its the first drawing you would come to (logical hey).

Now if we go to the Site Plan and turn off the sections/elevations or charge our "hide at scales coarser than" parameter so as to effectively turn them off in this view. Our sections and elevations are now magically updated to reference back to 030 (this is assuming that they are new construction phase sections and elevations). Again because its the first drawing you would see the markers when looking through the set.

If you're anything like me, I want mine to back reference to the General Arrangement Plan (040). So our dilemma is do we turn off the section & elevation markers in this view? (probably the obvious choice) or the alternative and probable wrong solution would be to adjust our set order so the general arrangement plan comes before the demolition plan in the set...

I look forward to a setting in Revit where we can override this behaviour in special instances. But understanding this may help you identify why sometimes a view is being referenced from a strange place.


I've also noticed some strange circumstances, usually when dependant views are involved where views reference back to a sheet that has the markers turned off. Hopefully this bug will be fixed or maybe it was just related to my file being corrupt?