How am I going to model this Octopus? ARCHICAD doesn’t have an Octopus Tool!

Previously we looked at the potential uses of Tools in general and how a Tool’s name can be misleading. While a tool might be named after its primary use, what the name implies is not its only use. At some point, the name of the Tool loses meaning. The “Wall” in “Wall Tool” vanishes. The definition of the “Wall Tool” becomes “a tool that creates a vertical or slanted element defined by a Reference Line  and a Fill, Composite or Custom Profile, that intersects cleanly in plan and 3D with a number of other elements via Priority Based Junctions, and hosts other elements via Window and Door Objects”. Obviously that is too lengthy (and probably incomplete), so it is simply known as ‘the Wall Tool’. But the name should give no preconception about its limitations.

“It ain’t what they call you, it’s what you answer to.” -W.C. Fields

Each of ARCHICAD’s Tools can be used to generate a wide range of geometries and each Tool has unique settings used to create those forms. Those same unique settings provide different ways elements created with the various tools can be edited once placed. Furthermore, elements created by the various tools have specific relationships to other elements (depending on what tool was used to create these other elements). Understanding these differences is instrumental in making the correct decision for a given modeling challenge.


Let’s explore the Wall, Column, Beam, Slab and Roof tools to understand each Tool’s strengths and limitations. If people want, we can do a follow up post doing a similar analysis of the other Tools—or explore further any of the individual Tools listed below. Regardless of the existence of that future post, you should be able to use the analysis below to understand the similar strengths and weaknesses of the various Tools.

The Wall Tool


  1. Walls are extrusions that follow a reference line vector at the base of the wall set at an established height to home story (or project 0).
  2. A Wall’s height can be linked to a story above its home story, making it dynamically linked to story settings.
  3. The reference line can be set to the inside or outside of the Wall or core (if a Composite is assigned to the Wall). For custom profiles, the reference line is established by 0,0 of the custom profile editor.
  4. A Wall can be vertical, slanted or double slanted.
  5. Walls can use a single Building Material, a Composite or a Complex Profile.
  6. Walls can be based on a single Reference Line, a tapered width from the Reference Line or a polygon plan shape (similar to the slab/roof tool).
  7. Walls can show on Home Story Only or All Relevant Stories (any Story that the Wall touches or extends to).
  8. Walls participate in priority based junctions with other Walls, Slabs, Beams, Columns, Shells and Roofs (the last two when merged).

Another important aspect of elements created by the Wall Tool: they can host Window and Door Objects. For atypical geometry remember that the Simple Window/Door Opening Object (formerly the Empty Opening Object) might be extremely important. Also atypical empty opening shapes are simple to create.

The Column Tool


  1. Columns are vertical extrusions based on a reference point set at an established height to home story (or project 0).
  2. Columns, like Walls, may be linked to a story above, making them dynamically linked to the story settings.
  3. The center point of the column may be linked to the center or any corner or edge center point of its core. For Complex Profile columns, the center point is defined by 0,0 of the complex profile editor.
  4. Columns may be vertical or sloped. Sloped columns top and bottom surface are always horizontal.
  5. Columns may be Rectangular or Round extrusions of a Building Material or be an extrusion of a Complex Profile.
  6. Rectangular or Round columns may have a finish skin applied to them.
  7. Columns, like walls, may show on Home Story Only or All Relevant Stories (any Story that the Column touches or extends to).
  8. Rectangular or Round Columns can be set to have Wall Skins (Finish or Other Skins only) wrap around the Column or be cut by the Column.
  9. Columns participate in priority based junctions with Walls, Slabs, Beams, Shells and Roofs (the last two when merged)—but not other Columns.

I want to digress and comment on point H for a moment. Patrick May (of many ARCHICAD related endeavors, of which noscriptgdl is his latest) helped me research these Tools posts. I love when I collaborate on articles because I get the chance to remember things I forgot, like Wall Skins wrapping around columns. Did you know this? Or forget it? I used it in ARCHICAD 9, but I’m sure I forgot about it sometime after ARCHICAD 11. The interesting things that can be done with this feature will require Patrick and I to collaborate on a post dedicated to just this. For instance, this feature is great for limiting the number of Walls. With Construction Method: Wrapped, we are able to get minor bump-outs in walls with just one Column and one Wall. Column skin wrapping or notHere’s another example, this time showing how we can use Columns with and without skin wrapping to change the thickness of an exterior wall. I’ve used a long column with my insulation + studs Building Material (with wrapping on) to create a section of fatter wall (in this case using a column that is 7 1/4″ wide by 4′-7 1/2″ long). I’ve then placed 1 1/2″ x 7 1/4″ columns using my dimensional lumber Building Material (with the Construction Method: Freestanding) to represent the studs for this area. I should have also changed the floor plan symbol type of the wood columns to display an X, but I forgot for this illustration.

2x6 to 2x8 studs

There are of course limitations and drawbacks to using columns to thicken Walls in this manner—hiding the Column hides the bump out, the skins Building Materials don’t show properly when cut in 3D or Section (you just see the BMat of the Column)—but those limitations can be worked with or overcome. Or those limitations might not matter for the situations where this is a good modeling answer. Either way, this is a good example of seeing how a Tool or combination of Tools can do what you want and then deciding if it’s the right solution.


  1. Beams are based on a reference line vector with a set height to home story or project 0.
  2. Beams have a set height or thickness below the reference line for the default square extrusions of Building Materials.
  3. Beams have a set width from the center of the reference line vector.
  4. Beams may be sloped or horizontal. Sloped beam’s ends always have vertical faces.
  5. Beams can use a single Building Material or a Complex Profile.
  6. Beams may be rotated around the X-Axis where the beam is a Complex Profile.
  7. The reference line may be offset from the horizontal center of the beam. Where Complex Profiles are used, the centerline vector is based on the 0,0 of the profile editor.
  8. Beams are more flexible than most tools, at least in terms of how many stories they are able to show on. Beams can show on Home Story Only, Home+One Story Up (or down), Home+One Story Up+One Story Down, All Relevant Stories, or All Stories.
  9. Beams participate in priority based junctions with Walls, Slabs, Beams, Columns, Shells and Roofs (the last two when merged).

Another important aspect of elements created by the Beam Tool: they can have holes placed in them (notice I said plural holes, as Beams can have multiple holes, each unique in size and shape).

The Slab Tool


  1. Slabs are based on a reference plane with a set height above home story or project 0.
  2. Slabs using a single Building Material have an adjustable thickness above or below the reference plane.
  3. Slabs can use Composites or single Building Material extrusions.
  4. Slab edges may be vertical or custom angle. Through the pet palette each slab edge angle and Surface is individually controllable.
  5. The slab reference plan may be based on the top or bottom of the slab finish or core.
  6. Slabs have all the floor plan visibility of Beams except “all relevant”, and an additional setting for “Custom” floor plan visibility and appearance. This makes them one of the most versatile tools for horizontally based elements that need to show on multiple stories (ie. stair parts).
  7. Slabs participate in priority based junctions with Walls, Beams, Columns, Shells and Roofs (the last two when merged)—but not other Slabs.

Slabs can have holes cut in them, but cannot host elements like Windows, Doors, or Skylights. However, there is some very interesting geometry that can be created using slabs, sloped edges, and/or curved sides: ramps, curb cuts, and tree stumps.

The Roof Tool


  1. The Roof Tool has a reference axis set at a given height above home story or project 0.
  2. The Roof Tool can be a single plane hinged on a single axis, like a sloped slab, or multiple surfaces joined around polygon sloping reference lines.
  3. Roofs can use Composites or single Building Material extrusions.
  4. For a single Building Material extrusion, a roof has a set thickness above the reference line.
  5. The slope of a roof is set by slope in degrees, percentage or n:12 units. Single plane roofs can have a slope of between 0 and 89 degrees. A multi-plane roof can have a slope of between 1 and 89 degrees. Note that only single plan roofs can be flat.
  6. A roof’s plan visibility is identical to the slab tool, with the addition of “All Stories”.
  7. Roofs participate in priority based junctions with Walls, Slabs, Beams, Columns, Shells and other Roofs (when merged).

Another important aspect of elements created by the Roof Tool: they can host Skylight Objects. For atypical geometry remember that the Simple Skylight Opening (ei the skylight hole Object) might be extremely important. A hole created by a Skylight offers different benefits from a hole created by cutting a hole in the Roof element. Additionally in Schedules, Roofs can list both the number of Skylights and holes. Slabs however can’t host Skylights—nor can ARCHICAD tell you how many holes they contain.

It’s ALMOST all the same

The lists above might feel repetitive, but look again. The tools often have similar but non-identical features. Think about the geometry you need to create and compare it to how each Tool handles element creation and management. Think about the display requirements of your elements and compare it to how each Tool handles visualization differently (beyond what’s described above, Surface control is different for each Tool as well). Or notice where all the similarities are. We always think about showing a Wall cut, but we can also show a Roof (but not a Slab) cut in plan. When might that matter?

When faced with a modeling challenge, ask yourself what aspects of the geometry can be described by the language of the various Tools. What visualization requirements are needed. If your geometry can be modeled with Shells, Roofs, Objects, or Beams, which Tool’s floor plan visibility options best meets your needs. Which Tool handles the sectional qualities the best. What about the element’s dimensions (you can control a Column’s length, width, and height via the Info Box but only a Beam’s width and height). And of course, remember to think about the future. Which Tool selection will make future changes the easiest. Remember that the same features that describe how and what can be created with a given Tool also determine how those elements can be managed after creation.

As our wall/column example shows, what you need to model might not be ultra fancy—it might not be something that can only be created with the Morph tool or externally via Rhino—but it still requires creativity to discover the best solution. We can create a 1′ x 1′ x 10′ tall form using all the Tools described above. The correct answer for that shape might not be a Column. The correct answer might depend on the floor plan visibility options, the ability to host holes, or the need for priority junctions to work with other elements that need to be Columns. Likewise, a similar 10′ x 1′ x 1′ long form might be best made using the Beam Tool, or perhaps the Column, Wall, Slab, or other Tool. It all depends on what control you need over that element over the duration of its existence.

Just because the shape you need to create looks like the Tool’s icon does not mean it’s the right Tool for the job.

In a future as unwritten post, we’ll look at these decisions through a different lens: data and schedules. After all, what really defines an element as a wall, window, or piece of furniture is not the Tool used to create the element but the Element Classification. If you pay attention to Element Classification and organize your schedules that way, then Tool becomes irrelevant to data organization (unless the Tool offers specific data functionality you need, like the hole counting example). But that discussion needs to wait for a bit….

Are you following Graphisoft North America on Twitter? Click Here to keep track of all the latest ARCHICAD News in North America (and beyond). What other tools should we cover on the blog? We could do similar breakdowns of 2D tools. Does that sound interesting?


  1. Steve Nickel

    Hi Jared…

    This a great series of tool explanations. The thing that I would add at this point is that the roof and slab tools are “polygonal”…that is, you can move the nodes around. Of course, I am “preaching to the choir”. Looking forward to Part 3.

    • Jared Banks

      Steve, great catch. Yes. That should be highlighted. But that’s probably a post in itself. The difference between reference line tools and polygonal tools. And the exception when the Wall Tool can be both. I’m going to have to think about if there’s a full post there. Because there are some critical differences.

  2. Ben H

    I tend to be reluctant to use beams because of the way they intersect with walls. Back a few releases I used a beam with a complex profile to model a complex curved roof. Unexpectedly, in certain scenarios it made the walls below it disappear because they were “intersecting”.

    Interesting trick using columns as studs to furr-out walls….

    • Jared Banks

      Ben, I find that I default to Beams for most things these days. Layers and Priorities can get tricky, but when they work, it’s so good! Floor Plan display is definitely their achilles heel. No cover fills. Sometimes goofy issues with Walls… I totally get that.

      For curved roofs, we need to remember Shells. I ALWAYS forget about Shells. That said, sometimes for curved roofs, I find Complex Profile Walls are actually a good solution!

      The column furr-out trick I think is especially nice for small projects or quick projects where the client might not need much more than a plan or some basic visualization. OR for during SD when the limitations of that technique don’t matter.

  3. Douglas Godfrey

    G. Roofs participate in priority based junctions with Walls, Slabs, Beams, Columns, Shells and other Roofs (the last two when merged).

    Not quite correct. Roofs have to be merged for PBJ to work.
    Hopefully that will change in future releases and Roofs will act just like a sloped slab.

    • Jared Banks


      Great catch. Clearly a typo from copying and pasting! I’ve already updated it to read:
      G. Roofs participate in priority based junctions with Walls, Slabs, Beams, Columns, Shells and other Roofs (when merged).

      Thanks for catching it. And yes, it would be nice if it were automatic. I assume the reason it isn’t is because we so often have conditions where we don’t want roofs to merge with other elements.

  4. Mats

    Great and helpful post that should be read by most users!

  5. Patrick May

    an additional trick for the column/wall relationship is to use identical building materials between the column and the wall core, and you get a clean floor plan view for a framed pilaster. This also works well if you hide the column’s layer, but leave the layer as intersecting, then the thicker wall works with window and niche’s. You can essentially reduce the number of wall composites needed, and you get a cleaner plan, elevation and 3d view from it.

  6. Cornelis Wegman

    You have lots of good advice. Here is another question: what is the easiest way to generate 3D stepped footings on a sloping site? I’ve done this using a combination of slab and beam tools, but there are all kinds of awkward bits that have to be included, such as overlaps of the stepped elements, piers under, etc. It took me a week to model on a simple house – hopefully, the next one will be faster – especially if I get some useful advice!

    • Doug Godfrey

      I model footings from beams. They are really quick, looks like I want it to in plan and in 3D and section it is perfect.

  7. István Talmácsi

    For me this article was not a novelty. But it was the proof of some fundamental problems of the ArchiCAD.
    In the ’80s it was a great idea to have these different architectural tools in a CAD software.
    But I think it is time to address the initiative to GS, to change it.
    There are too many restrictions and limitations about it.

    A way fewer tools would be quite enough!
    1) open polygonal for: all types of lines, walls, beams;
    2) fill-type for: fills, slabs, meshes, roofs, zones etc;
    3) object-type for: object, lamp, windows, doors, columns (without the restrictions of the openings to be only in walls – but every object could be placed into walls);
    4) dimensioning tools;
    5) referenced drawings/models: worksheets, details, sections, elevations, hotlink modules, stories etc .

    The elements created could be the same as now, and in the ui you could still have different icons for the different element-type presets of the tools (according to the present manner).
    In the tool settings it would be a switch of a new property of the sub-types (in addition to dozens of present properties it won’t be a big mess).

    And a few more thing:
    1) gsm scripting for everything, included the walls, lines, dimensions;
    2) component-like (or clone-like) grouping (like in sketchup and graphical softwares): in architecture it’s often when you need repetitive, identical elements; now in archicad you don’t really have a tool for this. It’s not stealing to use what’s working in other softwares.
    3) revamp the gsm language into an object oriented one;

    What would be the reason of it?
    1) fewer tools, by itself, is a good advantage;
    2) It’s often needed to convert from one to another. It would be a flip of a switch. No (real) need of the magic wand.
    3) No more insufficient restrictions.
    4) The software could be used as before; the new features would be additional, not replacing. The users won’t have to learn a new software.
    5) The iterative process of planning needs iterative solutions; a more open software is more iterative.
    6) A more open, a more iterative software is more robust, more useful.

  8. charlie brown

    Thanks, still a newbie and this helps. I often find myself fighting the object tool, stairs, roof, etc when I know the task would be long ago completed if in CAD – to create 2D construction document set. It’s hard to let go when you are trying to learn the best way to draw, and wanting to benefit from the power of BIM.

    • Jared Banks

      I always say “submit to ARCHICAD”. You can’t conquer it and tell it what to do until you listen to it and follow it’s rules. Have to learn the rules before we can break them, right? Isn’t that what we learned in architecture school? 🙂

      Don’t give up. I’ll aim to write more about the “I could do this faster in CAD” struggle. I totally get that and it’s a very valid point for new users. And it absolutely is a blockade that can hinder conquering the software. Fortunately the key to mastery is also in that statement. In short: BIM is a long game, both in proficiency and individual tasks. We should avoid situations where we are just doing one thing within BIM. Our actions should always be about multitasking. We should be slowly working on plan, section, and elevation at once. Or plan and schedule. Or arch and elec. Or SD and permit set…

      When we look at things that way, “faster in CAD” starts to hold less sway on us. Okay, now you got me REALLY thinking about a new blog post. Thank you for the comment and I promise, more on this topic to come!


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