Largest project acchived in BIM.

[Anonymous]

Hello everyone. AC, Revit, VW, AP users. I work in construction company. Right now we came across big (1.2 mil sqft) hospital project, and together with architects looking for best BIM software that will be able to run this project. Right now we are testing Revit (mostly because of architect) but when project goes into 250 kilo sqft hardware starts to say NONO (experience from other projects). It's a big problem. Hardware is not the problem (state of the art for today standards). Any experiences in that area?

[Djordje]

Take a look at Eureka Towers, by Fender Katsalidis, in Australia. I would think that it is a lot bigger than your project. There used to be an extensive article on the Graphisoft site.

Explore IFC export of Revit, and its import into Archicad. You will need it.

[TomWaltz]

I think the largest I have worked on myself is about 120,000 SF.

edited Nov 5, 2007: OK, bump that up a bit.... my current firm averages 500,000 SF or so....

[Dwight]

Think of me as a schludense, but:

Who cares how many square feet the project is? That is not what is going to make it "big" or difficult from a computer standpoint. How much building detail will there be? Especially in 3D? Making the machine haul everything around all the time is what bogs a system down.

The question, as with any sizeable project, is how to manage layer sets to view only task-relevant material so that graphics displays can remain snappy and saves can be quick. I'm happy to be corrected by thoiose with more experience, but when I encounter a problem project, it is because the user hasn't enough RAM, disk space or element view discipline, NOT because the program couldn't handle it.

Be sure to assess REVIT's layer/view management against what Archicad does.

[Karl Ottenstein]

Dwight wrote:
Who cares how many square feet the project is? That is not what is going to make it "big" or difficult from a computer standpoint. How much building detail will there be? Especially in 3D? ...

Exactly. The new polycount addon (Goodies) for AC 10 is a good way to check the polygon count for your model, an aspect that will slow things down.

Today's reality is that we still need to think about the LOD (level of detail) of our models in order to obtain high performance. With future hardware and fine tuning of software, this will be less of a concern in the future.

Example: a firm was experiencing a 5 minute delay in the generation of the 3D window for a large multiuse project. It turned out that they had 1700 windows that were all set to a high level of detail for frame, trim, etc. - producing a very high polygon count for the total model.

Sure, that's how we'd like to model - but the reality is that the high level of detail will only be visible in details, enlarged building sections, and perspective views where those windows are "close" (relative term - depends on DPI and final output size) to the camera. High performance was returned by changing all windows to 'simple' except the windows that matched the kinds of situations just mentioned.

No doubt similar tricks will help in Revit, although I've heard that Revit bogs down at lower polygon counts than ArchiCAD. (Don't even try it in SketchUp - it bogs down at pretty low polycounts.)

Cheers,
Karl

[Dwight]

But Polycount only addresses the 3D model.
And you don't need to count polygons - you need view discipline - it is all relative.

I'm also concerned for the absolute number of elements the 2D engine needs to render, because that is where you spend your time with a large project - lot of labels and text, eh? and speed here is again achieved by creating the right layer view sets.

So many users are like Little Red Riding Hood gaily skipping off into the forest with her little basket of port, pate and porcupine pie for Grannie, they forget to manage graphic information and get seduced by the wolf.

"La la la la la. Ouch."

Of course it is the new millennium so anything can happen. I know that in 2007, Little Red Riding Hood, confronted by a talking, standing wolf dressed like a man would think "No stringy Grannie guts for him. If he lets me manage his act in Vegas it will be venison every night for both of us."

[TomWaltz]

all true, but you don't see many architects listing their project work by polygon count... it's likely their concern will be "Can Archicad handle a job of XX square feet", not "Can Archicad handle a job of 100 Polygons per square meter"

[Karl Ottenstein]

Dwight wrote:
But Polycount only addresses the 3D model.
And you don't need to count polygons - you need view discipline - it is all relative.

I'm also concerned for the absolute number of elements the 2D engine needs to render, because that is where you spend your time with a large project - lot of labels and text, eh? and speed here is again achieved by creating the right layer view sets."

Hi Dwight,

I've never received a report of purely 2D elements (text, etc.) causing a performance problem. (Those 2D elements that are projected from 3D elements are another matter.) Have you or anyone else had seen text cause a performance problem (on a current computer)?

Absolutely agree about proper layer management, of course. For large models, this sometimes means creating layer combos that do not correspond to the final output drawings, but to working views that will perform quickly.

Another performance tip for large-project people is the 'show elements in 3D' dialog. Suppose those windows that bog everything down really must be in the level of detail indicated. Users should remember that they can turn off windows/doors (for example) in that dialog - and then see just empty openings - to speed up other 3D work.

Cheers,
Karl

[Dwight]

TomWaltz wrote:
all true, but you don't see many architects listing their project work by polygon count... it's likely their concern will be "Can Archicad handle a job of XX square feet", not "Can Archicad handle a job of 100 Polygons per square meter"

Let them talk.
We know the secret.

New measure of efficacy: p/m2. hahaha.

[TomWaltz]

Dwight wrote:

TomWaltz wrote:
all true, but you don't see many architects listing their project work by polygon count... it's likely their concern will be "Can Archicad handle a job of XX square feet", not "Can Archicad handle a job of 100 Polygons per square meter"

Let them talk.
We know the secret.

New measure of efficacy: p/m2. hahaha.

Karl must be working with a new client... that explains the helmet 😉