Friday, December 16, 2011

To Host or Not Host

This isn't asking about a Xmas party or dinner party. This is a frequent topic with anyone digging into making content seriously.

Usually the bias is toward defining the answers according to architectural needs. No offense intended, whoever is asking the question is going to have some bias. I spend as much or more time these days dealing with the "other" disciplines and this question.

If dealing with the other disciplines, the typical quick answer is usually face-based as well. True if we assume a Revit to Revit consulting relationship. If an engineer wants to use their cool new software (Revit of course) and their architect isn't using it then a face based family will need a face that isn't there. With a solid library RME can be quite effective even without an RAC model (though a bit harder without something to create spaces in). In this situation we can't just put those families on the level's work plane because they won't be oriented correctly. A reasonable argument (I think) can be made for families that are not hosted at all, even if assuming an engineer is dealing with "your" architectural model linked into their project.

To be most flexible, as "crazy" as it might seem, the answer may be starting with non-hosted content. Yes, it is nice to have a family follow "your" walls when they move (face-based will). Yes, with non-hosted content you may have to move (more) things when designs change. Change quite often isn't just a wall sliding left or right, it can also mean a completely new wall or walls or a different layout entirely. When the original host gets deleted the orphaned face-based family ends up "wanting" a new host and resolving that is usually an onerous (not difficult) task too. A family that isn't looking for a host won't move automatically but fixing that situation isn't really any harder, all that different a task or substantially more work when you compare the "doing" of the tasks.

Then there is the notion of "close enough", which freaks people out too. Consider a electrical disconnect (device) can be six inches, eight or twelve inches from the equipment it supplies power to and it is still close enough. If the equipment moves a "little", no harm done...the disconnect is still fine where it was when you put it in originally because the "whip" the electrician installs between them will deal with the difference. Most engineering solutions have room for "slop" at the end of (at least somewhere along) the system. They have to design in something to deal with the construction reality on site. It seems reasonable to me to mimic that where appropriate/possible in our modeling effort.

The perfect answer, the one solution that fits all situations doesn't really exist at least not one that fits every firm or project. We might get close for one firm or discipline but each project brings new conditions to consider. It's more work but it may come down to having complete content libraries for each condition rather than only having one solution focused on one approach.

3 comments:

phil-osophyinBIM said...

Steve,

Thanks for your post.
I am investigating this for the next wave of setting up new content for my office. I recently asked a similar question on Revit forum
http://www.revitforum.org/architecture-general-revit-questions/5540-face-based-vs-wall-based-vs.html
and trying to get people's feedback.

Philip

stimmo520 said...

Our office is in the midst of creating all of our own content, and one of the prerequisites is to be non-hosted. We have been burnt too many times hosting to walls that were removed. Plus, it makes the modeler check his/her work a little more cloesly.

Aubrey Frederick said...

Hey Steve,
I know i'm super-duper late on reading this blog posting, but it did help answer some questions I had about hosted vs. non-hosted.

Thanks again for spreading the knowledge and reasoning behind it.