Reuse of model elements

[Duncan Lithgow]

I have to make some decisions about how to implement repeating elements in my building. For example, there are stairs, elevator cores and facade elements that are repeated in the project. I understand that I have three options, here are my thoughts

1. Load as groups
Advantages: Flexible joining to rest of building mass. Can be reloaded as links. Easy to extract quantities.
Disadvantages: High risk that users will change things. Loading groups as Project Files can pollute host file if they are not from the same template. Must be reloaded manually. Groups as units cannot be scheduled (there are workarounds). Seem difficult to manage for users, quick descent into chaos.

2. Links
Advantages: Can't be changed in host project. Low performance cost. Reloads 'automatically'. Links themselves can be scheduled.
Disadvantages: Can't be changed in host project, Wall joins/Door placement problems etc. Tricky to take quantities correctly.

3. Assemblies
Advantages: Easy and flexible. Can be scheduled both as units and for quantity takeoff.
Disadvantages: Very easy to change in project. Only exist in project (no reloading options).

This is a new issue for me, and one with potential for a massive impact on this project. So please correct my ignorance and help me find relevant reading. I'm struggling even with finding relevant terms and vocabulary (my working language is Danish).

[dhurtubise]

Can you give us a bit more info. Are we talking about a single building split in different size, several buildings sharing the same elements?

[Duncan Lithgow]

At the moment it's one file in a sketch phase after a quite detailed competition project for a hospital project (http://www.cfmoller.com/r/Vinder-af-nyt-supersygehus-i-Koege-i13259.html). I want to standardize things like stairs, facade elements, technical rooms with shafts, elevator cores. But basically I want to understand the issues involved and the tools at our disposal so I can make the best possible choice for each part of the project.

In time this file will be broken up into at least 5 BIMs - but some of their content may be links containing standard solutions.

[dhurtubise]

In our case most project(we rarely work on small ones) use a Vertical Circulation file. This file contain the stairs, railings and all needed elements and is then shared through the entire building.
Different building is then a different story

[Duncan Lithgow]

I know that the last campus hospital I worked on started that way, but then the placement of doors was different from the different stair wells so the system broke down. How do you tackle things like that? I'm thinking that one could just make the necessary walls unique to each placement and placed in the project.

Would you consider using groups loaded as links? Have you ever tried that for 3d elements of this type.

Do you do your stair drawings from the vertical circulation file or the project?

[dhurtubise]

The vertical circulation also encompass the core walls. That way the doors are identified in that file and easily coordinated within arch and structure.
Stairs (or any vertical circulation sheets are in that file)