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View Full Version : Architectural Revit and truss... How are you guys supposed to do it?



scowsert
2010-01-18, 11:28 PM
Hello, I'm a Revit Structural Guy teaching a Revit Architectural class. Up until the latest advantage pack you guys didn't get the truss tool (not that I'm a big fan of it). How did you deal with trusses in your models if you weren't working with Structural? In an upcoming class I'll need to show them how to do standard premanufactured wood trusses.

I'd like to take them down the best road for this but quite frankly non of them seem all that great. I'm tempted to tell them to just draw it in their section and don't bother with modeling them.

Thanks Sage (popping his head in from the structural forum).

sfaust
2010-01-18, 11:35 PM
We use custom families for the standard types. not great, but we don't do wood trusses that much either...

scowsert
2010-01-18, 11:39 PM
That really seems like the 'best' way (man I hate the truss tool). I think I'll push it off till next quarter when we go over custom families. That could be a pretty good one. Slopes, EQ. dimensions based off reference planes.

twiceroadsfool
2010-01-19, 12:46 AM
Custom Families are a great way to do it, if you have time/someone to make custom families.

At the end of the day, the bigger questions is: Is it in the architectural scope of work to detail them?

Thats really the question you need to answer first. If the answer is yes, then of course you need some custom families, or a ton of framing members to stick build them in the project.

If youre NOT the one holding the bag for detailing them, you need to seriously consider what you need to get out of them, and how you proceed. For instance: I would give SERIOUS thought to using walls of the prescribed thickness for them. Why?

1. Its very fast. Put in a wall at the correct base height, and array at correct spacing. Grab walls, attack to roof.
2. Filters will take care of the walls scheduling and being in places i dont want them in. As *old school* and unBIM as it is, Revit can go VERY VERY far on just some sensible naming conventions and Filters.
3. They will clash detect with EVERYTHING running perpendicular. Which i want them to. I dont want to clash detect check or interefence check, or have my MEP guys designing around a fictitious toy truss that i modeled in Revit so everyone ASSumes its correct, when its merely *the intent.* Using a Thin wall with a specific material takes care of all that.
4. Performance. Theyre lightweight.

Rereading your post though, it sounds like you might mean if were building the model because the engineer simply isnt in Revit and we want the model for our own drawings. In that case, we decide if its worth modeling those trusses, or using DC's in section. I try to model all of it, as i know its just a better/faster way to do it. But with a custom truss, a quick cost/benefit discussion happens if im not available to build someone a custom truss.

Of course, im finding the few trusses that ship with RST can be shoehorned to do alot, LOL...

scowsert
2010-01-19, 12:53 AM
twiceroadsfool - The goal of the class is to get these folks ready for the real world. I think it would be wise to bring up all of those points that you made. Heck perhaps even show them both ways to get the job done. I made the point when doing floor framing that I wouldn't necessarily place every joist. I depends on the the project and what you are doing with it. Down and dirty, no... cost estimating sure it just takes more time. Does your project require it?

So your walls as trusses, do you edit the profile to show the webs or are they just triangles that will be detail lines in your sections? I recall reading a thread on here talking about using walls as trusses. I like the concept a lot. Walls attach really nicely too the roof, would display hidden lines on a roof framing plan etc...

twiceroadsfool
2010-01-19, 01:10 AM
Showing the truss webs- in a condition where you arent actually the one detailing/designing them- is precisely what my intent is to avoid. If webs and gaps are there, people start thinking "thats the design." Suddenly Mechanical contractors are plumbing ducts weaving in and out of webs, Architects are stringing track lights evenly spaced in a room through the joists, Sprinkler piping runs twist this way and that. A solid wall means everyone hits it, and it makes them say *hey, thats not really going to be solid... Whats it going to be like? I guess i have to find another drawing...*.

Its just another check and balance. It still falls short if people flat out arent paying attention, but in the real world (ive found) people really need to be asking "is this my task," before they model something. Not to skirt responsibility, but because more often than not your task is to COMMUNICATE something to someone ELSE, than it is to simply model it to the hilt in your model. :)

Elmo
2010-01-19, 07:51 AM
Truss+ from tools4revit is most likely the best I have seen for a solution.

http://www.tools4revit.com/