Joining geometry - why not automatic

[radu.grosu]

I wonder why Revit does not do that automatically. When an element intersects another, one of them must let the other one pass trough. Only a hierarchy (organized on types and instances) should be established once for Revit to know without asking twice from whom to cut out geometry.
Just thinking out loud.

[Calvn_Swing]

I like the idea in principle. I would like to be able to set hierarchies for many things in Revit, and have them follow my rules rather than some rules I can't control. However, what about those few atypical conditions? You need to be able to override said rules easily enough. My two cents...

[comhasse]

I've been wanting to ask that question for a long time myself, because it seems so obvious. This is what Revit does with intersecting walls already, which answers the question about the atypical conditions: "disallow join"-option and "edit wall joins"-tool solve these problems. And actually it should even be easier to establish a hierarchy between a vertical and a horizontal element (wall and slab) compared to two walls (most of the time the slab will cut the wall for obvious reasons, whereas between two similar walls the choice is often somewhat arbitrary).

Edit: Thinking about it, REVIT has to establish the hierarchy already if i join manually and it does - it cuts the wall. Between structural columns and slabs it seems to be variable, my german ootb families cut the slab, the international ones are cut by the slab. I couldn't figure out what this depends on.

I'd would really love to hear the insiders about this. Is it a design choice or a technical difficulty? Anyway i think this should be a wishlist item. Aside from the time saved cleaning up sections with the join tool, this would would allow for much more accuracy in material take-offs. Unjoined geometry can very easily be missed in a complex model.

[nosslok]

Just thought I would post this from the help menu for what it's worth:

Walls cut columns.
Structural elements cut host elements (walls, roofs, ceilings, and floors).
Floors, ceilings, and roofs cut walls.
Gutters, fascias, and slab edges cut other host elements. Cornices do not cut any elements.

To my experience so far when joining two similar items (i.e. walls embedded in walls) the first pick is the "cutter" and the second pick is the "cuttee". You do have some control in this particular situation.

KCO

[comhasse]

I still think this is such an important subject, that i would like to hear a statement from someone of the REVIT development team ;) about it. In the mean time, here is a work-around for at least one case of this problem:

When i edit a slab, then finish the sketch mode, Revit detects interferences with Walls and asks if the overlapping volume should be cut out of the walls (i.e. if walls and slab should be joined, right?). So in order to clean up the model i enter the edit mode for each slab, close again and answer "yes" to that question. This is not exactly elegant but still faster than joining each wall with each slab. (I don't have Revit on this computer, so right now i can't tell if this only applies to walls that touch the slab at the periphery, i.e. usually exteriro walls.

[mibzim]

Walls cut columns.
Structural elements cut host elements (walls, roofs, ceilings, and floors).
Floors, ceilings, and roofs cut walls.
Gutters, fascias, and slab edges cut other host elements. Cornices do not cut any elements.KCO

Nosslok
We had that problem a while back with walls cutting columns. It not really what you want them to be doing. Eventually discovered that a STRUCTURAL column is way different from an ARCHITECTURAL column. Architectural columns will be cut by walls (and will adopt wall material by design), but its the opposite with structural columns - they will cut walls.

[dbaldacchino]

Architectural columns are meant to be covers for structural columns. If you don't want them to join to your walls, all you need to do is edit the family, go to Settings->Family Category and Parameters and uncheck the option "Automatically joins geometry to walls".

[mibzim]

there you go - thanks david