Ceilings- how do you model them?

[Mats_Knutsson]

Ciao smarties,

How would you model ceilings meeting the following export IFC-model criterias?

* Ifc BaseQuantities for IfcCovering: (gross area, net area, width (thickness in the case of ceiling))

* Holes in ceiling - yes happens (shafts, columns, walls)

* Structure - always (ok with rectangular profiles)

Basically a simplified ceiling with it's Ifc Base Quantities...

Best regards,
Mats

[Erwin Edel]

Slab or roof tool generally. Slab tool if the whole project has horizontal ceiling, roof tool for all ceilings if there are also sloping ceilings.

If you mean for tile based system ceiling, haven't done any of those in a very long time, but I suspect the overhauled curtain wall tool offers you a lot more options in ArchiCAD22. Also in 22 you have quite powerful tool for definining custom properties and by setting up IFC mapping rule, you can probably get some good results there: make a custom property based on a rule >> map the IFC property from the custom archicad property.

Regarding holes: if they are there for MEP, I would use an object to define the hole. If it is just a big hole in the design, model the hole.

[Mats_Knutsson]

Erwin wrote:
Slab or roof tool generally. Slab tool if the whole project has horizontal ceiling, roof tool for all ceilings if there are also sloping ceilings.

If you mean for tile based system ceiling, haven't done any of those in a very long time, but I suspect the overhauled curtain wall tool offers you a lot more options in ArchiCAD22. Also in 22 you have quite powerful tool for definining custom properties and by setting up IFC mapping rule, you can probably get some good results there: make a custom property based on a rule >> map the IFC property from the custom archicad property.

Regarding holes: if they are there for MEP, I would use an object to define the hole. If it is just a big hole in the design, model the hole.

Can't do slab or roof...I need the profiles... However slab and roof can give med the correct base quantities...pity I always need to model the framing...

I'm on 21 and neither 21 nor 22 can't (!?) do holes in CW thus no net area... also CW does not have IfcCeiling Base Quantities.

[agroni]

I also model it with a slab, and for that only the lower part that is going to be visible. I don't model the construction because it varies from one producent to the other and also this parameter can be scheduled based on how many m² you have.
I use the slab and wall and classify them as IfcCovering Type CEILING.
For cut openings i use the cut opening library (at least in the Austrian version), since there are exported as an opening in the IFC.

[Da3dalus]

We have quite a few designers that now prefer drawing suspended grid ceilings with the Curtain Wall tool. It does have advantages. Our "standard" method is to use Slabs, and we apply a 3D Grid Accessory (which is limited in geometry) to the Slab using one of the Goodies. However, I've also found some downfalls:

1. You cannot use the Magic Wand to define the boundary, like you can with a Roof or Slab.
2. The Curtain Wall has no opacity or Cover Fill when used in plan. It appears to always be transparent. This is a problem if you are using partial ceilings, and wanting to show overhead exposed structure or ductwork, and hide it just where the ceilings are.
3. Each "stick" of the curtain wall is a separate member, which is a Complex profile, as is each panel. The adds significantly to the processing power, and is only partially mitigated by limiting the detail in the Model View Options. It's especially a file size problem when exporting to IFC for consultants or some other 3D format for rendering. In contrast, the Ceiling Accessory is very simple.
4. Getting ceilings to appear in IFC-to-Revit as actual Ceiling category elements is already difficult using Slabs (hint: Link the Ceiling IFC into Revit, then Bind and Ungroup). When using Curtain Walls, it's almost impossible.

I'd love to hear more thoughts on this. It occupies a great deal of my days!

[James B]

Da3dalus wrote:
1. You cannot use the Magic Wand to define the boundary, like you can with a Roof or Slab.

This video (hopefully the link works with the time position in the video) can help re Magic Wand.

[Aaron Bourgoin]

@Da3dalus:

re: "4. Getting ceilings to appear in IFC-to-Revit as actual Ceiling category elements is already difficult using Slabs (hint: Link the Ceiling IFC into Revit, then Bind and Ungroup). When using Curtain Walls, it's almost impossible"

Slabs are what we use typically for ceilings and bulkheads in the condo towers we design. I followed your suggestion about the binding and ungrouping, but another problem remains which is that the construction manager we're working with doesn't see elements associated with a storey or level.

I'm going to send him some instructions to bind and ungroup rot see if that's enough to solve his problem. But, are you aware of this associativity issue and if so, have you got a fix for that?

[miki_vukcevic]

@Mats_Knutsson ,

Here is a tutorial, from which I always do ceiling based on it, and never had issues with that.

Also for all holes you have in Object tool libraries to put on ceilings - lamps, ventilations, air conditioners, holes etc.

 

Watch the ceiling tutorial, or maybe I didn't understand what you needed. 

https://www.youtube.com/watch?v=aJNulKwpnX0&t=860s

 

[miki_vukcevic]

Or you can use this tutorial for the super YEEYY wood ceiling.

https://www.youtube.com/watch?v=OmkmlHcmD8Q