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Modeling
About Archicad's design tools, element connections, modeling concepts, etc.

Foors and ceilings

Anonymous
Not applicable
I'm new to Archicad and need some help building floors and ceilings. I've been reading the documentation and playing around with the application, trying to figure things out on my own, but this doesn't seem to be addressed anywhere very specifically.

I want to make a floor with 2 x 10 floor joists. What's the best way? Should I be using the slab tool or putting in separate joists with the beam tool or is there a better way altogether?

Thanks in advance,
Wrathchild
5 REPLIES 5
Dwight
Newcomer
You are confronting the fundamental dilemma of BIM: how much to model.

Most users develop a sense based in the fee and in whether the design is actually supposed to solve all of the problems or whether implied solutions are adequate. Conventional buildings should need less modeling since you might already have details for most conditions or expect the trade to solve it [or call you to yag on what to do, consuming your drinking time].

If you are going to provide numerous building sections that locate joists and actually solve all of the framing issues, then model the frame. The process will also tell you something useful about design problems.

Modeling the joists as beams is the same effort as making a framing plan, so if that is in your work scope, then modeling joists pays off in other views. For instance, to model the joists and then extract three cross sections saves you the trouble of placing joist symbols three times and will update when the design changes.

There might be framing add-ons that place joists automatically, but they don't necessarily conform to all building codes.
Dwight Atkinson
Erich
Booster
Dwight got it spot on. The only other thing I would add is that it what and how much you model may well depend on where in the design process the project is.

If you are only working in schematic design with the building plan and form changing regularly, then perhaps using slabs would be preferable to modeling the framing....

Just more food for thought
Erich

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Anonymous
Not applicable
Thanks guys, I think I get the picture.

Basically, what I'm hearing you say is if I'm drawing more for presentation type uses, slabs are fine......but if I want to have accurate bills of materials and so forth, I need to put in all the pieces.

Any other input will still be appreciated.
Dwight
Newcomer
You'll never get an accurate bill of materials no matter how well you model, but you can use the different quantities to compare relative costs of different alternatives because they will both have similar fudge factors.

The real reason for accurate modeling is under the surface: positional and assembly data. Where things go in relation to each other, where they do and don't meet in space. Where you hit your head on the stairs. Ducts thru beams. Stuff like that.

AND putting a thing in a model once gives you all the other views. This is especially useful when you edit the building.
Dwight Atkinson
Anonymous
Not applicable
Dwight wrote:
You'll never get an accurate bill of materials no matter how well you model, but you can use the different quantities to compare relative costs of different alternatives because they will both have similar fudge factors.

The real reason for accurate modeling is under the surface: positional and assembly data. Where things go in relation to each other, where they do and don't meet in space. Where you hit your head on the stairs. Ducts thru beams. Stuff like that.

AND putting a thing in a model once gives you all the other views. This is especially useful when you edit the building.
I definitely agree with that last part. I've worked with other modelling programs in the past and find that to be a big benefit. So far, in working with ArchiCad, I think they do it better.