Category Archives: Level of Detail

File Performance – Self Audits

Projects are routinely audited, or at least reviewed on the BIM Server to maintain a reasonable quality of model performance and accuracy. There are specific areas of the audit that are responsible for file performance. Some of these audit sections are worth paying attention to because they can affect file navigation, others can impact general teamwork performance. In any case, these areas of the audit are worth periodically reviewing, even between formal audits.

The areas that need to be self audited are:

  1. The Library Manager
  2. The Library Loading Report
  3. The “Error” Report
  4. The Drawing Manager
  5. Solid Element Operations
  6. Total Model Polygons
  7. Attributes

Library Manager

The Library Manager needs to be periodically reviewed for organization. A disorganized Embedded Library is difficult to maintain, manage, and review. More than the organization, the contents of the Embedded Library are a critical element to file performance. Because the E/L is part of the file, rather than linked to the file like a BIM Server Library, it directly impacts the overall file size; even if content is not placed in the model. Ideally, .gsm content embedded in the file should be less than 10 MB and images used for surfaces should be less than 1 MB. These should be the targeted max for embedded library content. The more frequently an object or image is going to be used in the model, the smaller the file size should be.

Library Loading Report

The library loading report will appear when first opening/joining a file if there are any library issues. These issues may include missing, duplicate, or substituted library content. It may seem like this is just something to close out of and ignore, but this palette is warning that your model may be suffering from poor performance and accuracy. For more on the Library Loading Report, see this WWABIM post here.

Error Report

The report tab will come up when there is processing error in any non-plan model Viewpoint. Like the library loading report, it may be tempting to ignore this tab, but this report is a warning that your model is suffering from invalid geometries, missing attributes, or other errors that can not be resolved. If there are too many errors in the model, the result can be beach balling, slow send/receive, and slow navigation between Views. To review how to clean up Error Report content, see this WWABIM post here.

Drawing Manager

The Drawing Manager often suffers from missing content. Although missing content here may not slow a file down noticeably, the drawing manager is a good place to review externally linked content such as .dwg & .pdf files that have been dropped onto layouts. The drawing manager is a good place to review the update status of content on layouts, which can speed up layout book navigation. This is also a good management tool for tracking external content’s paths to review linked content file size. Linked drawings with large file size can slow the model significantly, and even more so if large files are embedded in the drawing manager. Always review pdf/dwg file size before embedding in the drawing manager. For more information on the Drawing Manager see WWABIM posts here and here.

Solid Element Operations

Solid element operations have been reviewed in past WWABIM posts here, here, and especially here, as well as in a previous internal DD L&L. In running self audits, any element with more than 100 connections should be reviewed, with any unnecessary targets, operators, or other connections removed.

Total Model Polygons

The most important aspect of a model’s performance is often the number of visible polygons. But even if layer and view settings are carefully managed and reviewed, you may run into situations where the entire model needs to be viewed, or may be accidentally viewed. If there are too many polygons in the model, this may result in an slow file performance, beach balling, file or computer freeze up, or even a file crash. With our current hardware, we should be aiming for no more than 5,000,000 polygons for a standard file.

It may not always be a clear line, since the source of polygons as important a role in file performance as the total polygons. For example, in some basic tests and overall experience, 60,000 polygons from a single mesh can perform worse than 1,000,000 polygons from objects. Also, 3,000,000 polygons from a single library part (object tool) placed several times will perform significantly worse than 3,000,000 polygons from 50 different library parts. In general objects contribute to the most polygons, but GDL also handles polygons significantly better than other tools. Overly complex mesh elements and excessive use of morphs can be a bigger performance issue to a file than objects.


Attributes can have a huge impact on file performance, as well as document and output file sizes. A large, complex, custom cut or drafting fill can result in an incredibly large pdf or dwg file; in some cases so much so that the files can not be emailed or, in many cases, even printed/plotted. Additionally, custom profiles can result in poor model performance if not properly applied to the model. Profiles applied to walls should be used sparingly, as the intersection between walls results in excessive polygons and slow model performance. Custom profiles are better applied to beams, instead of walls.

The last part of attributes that should be self audited is the naming and file size of the attributes. If surfaces are using large images, it can slow the file down (see Library Manager above). Beyond the image size, the image naming of surfaces is critical to BIMx output. See the WWABIM article here and here for more information on BIMx surface errors.

The Often Neglected Basic Shapes

I think the Basic Shapes often get ignored. These library parts are great as place holders or substitutes for tedious to model objects, basic element massing, or even final model elements. The grid object is great for register and vent grills and grates, drain screens, ceiling grids, trellis elements and more. Some of the other shapes can be used as object massing, or even a starting place for generating custom objects. Creating curved elements directly with the morph tool is possible, but they typically turn out blocky and faceted looking. Starting with a Cylinder, Cone or Sphere allows you to set the resolution of the curves, then convert to a morph to edit or incorporate with other morph elements.


Some of the objects in this folder may be useless and tacky (the House Model & Conceptual Tree Model for example), but most of these elements can be a dynamic part of modeling complex model elements or even schedule-able place holders for elements that we may not see in the model; such as hidden appliances and plumbing accessories. I recently used a few of these elements to model an exposed sink trap for a bathroom, and it was much faster than trying to build it with beams and columns or morph elements.

The last thing to consider is that these objects often have settings beyond the obvious. Some have settings for adjusting number of faces, curve resolution, overall and individual dimensions. This allows a polygon prism object to accomplish a wide range of geometries, for massing elements as well as trimming elements as a dedicated operator.

Just keep this little library folder in mind next time you are considering building a new custom object, fixture or accessory.

Relevant Stories

Everyone should be familiar with the Floor Plan Display settings for the various element types in ARCHICAD. Some tools are very flexible in regards to which stories they are visible on, others seem very limited; namely the wall and column tool. With these tools, you only get two options; Home Story Only and All Relevant Stories. So what constitutes a Relevant Story?

For this example, I have just thrown together a couple walls in the ARCHICAD20 Residential Template, but it illustrates the point well enough.Screen Shot 2016-07-26 at 4.46.32 PM

The boundary walls are 12′ tall and extend 2′ to the the story above. The bisecting wall is 10 feet tall and is top linked to stop at exactly the story above. All walls are set to show on All Relevant Stories.

The resulting floor plans are as follows (Home Story left, Above Home Story right):

If this is not showing how you need or expect it to you can adjust the view settings to determine the constraints for a Relevant Story in the view map view settings.

Going to the Roof Story’s view settings, go to the 2D/3D Documents section and click on Floor Plan Cut Plane Settings…

Screen Shot 2016-07-26 at 4.32.14 PM

From here, you can define what extents will be considered relevant for this view. If I want the boundary walls to show as cut instead of outline as illustrated in the plan views above, I can drop the Cut Plan height to Current Story to a level that will cut the outer walls. Then if I want to include the interior wall as an outline element (not cut through), I can set the Relative Floor Plan Range: Show down to: Current Story -2′ (or any height that would include this wall.

Screen Shot 2016-07-26 at 4.32.21 PM.png

The result is that the home story for these walls has not changed, all walls are shown as cut just as before, but the story above shows with the taller walls cut and the lower wall as outline only:

One of the amazing advantages of this feature is that a wall may be Relevant for one view, but not for another. Even though the story settings match, the wall height never changes, but the wall appears on one plan view, but not another of the same story. Or it appears as cut in one plan view but as outlines only for another view of the same story.

The default for our floor plans is to have the Cut Plan height to Current Story set to 4′, and all offsets set to 0″, but there are always cases to fine tune this to show or hide elements, or change how certain elements may show in a given view.


Integrate a Trim Reveal Into Doors/Windows

On occasion you may want to pull the interior finish of a wall away from the trim/frame to show a reveal. In the past we have done this with a beam/column/morph SEO around each opening. Now, thanks to a strange glitch in a project, we can replicate a reveal integrated into the Cadimage door and window settings.

First, in the window/door settings, open up the “All Parameters…” drop down from the top of the Cadimage Window – Settings portion of the selection settings.Screen Shot 2016-04-13 at 10.52.18 AM

Next scroll down until you see a drop down for Composite Skins. You can adjust the offset from outside of frame (Wall Hole size), to the position of the composite skins finish.Screen Shot 2016-04-13 at 10.52.36 AM

Once the trim position and frame dimensions are correct, the result for this example is a trim that is flush with the interior face of wall finish, but with a 1/2″ reveal to the trim width.Screen Shot 2016-04-13 at 10.50.47 AM

A couple of things worth noting on this setting:

  • This is a uniform reveal for all sides/top/bottom of the window or door’s relationship to the wall that it is hosted in
  • This is not measured from the trim position, but from the wall hole, or outside edge of the main frame

Smarter BIM with Labels

Precise Model needs to be documented precisely, with as many “smart BIM solutions” as possible. This means elements that update seamlessly to provide information that is as precise as the model.

Manual text and overwritten dimensions are examples of bad solutions that will make sloppy modeling tell a misleading story. There are rare cases where these are unavoidable, but there is usually a smarter solution.

I have been looking at improving our template with as many smart BIM elements as possible. Today I took a look at labels and annotating RCP’s. The new AC19 label types include a label for annotating the elevation of ceiling slabs. Since our RCP’s are created from 3D documents, this ties the bottom or finish surface of the slab to its home story.Screen Shot 2016-01-25 at 2.32.49 PM

I tested this out in a few projects. We can get this label to graphically appear similar if not identical to our current text over RCP solution. With this label, not only does the annotation link to exactly what is modeled, ensuring precise modeling, but it updates with design changes, making it a smarter BIM solution.

Screen Shot 2016-01-25 at 2.33.00 PM

In the project above, I tested this out and actually found a discrepancy between the intended ceiling height and the actual modeled ceiling height. This is a clear example of the benefit of a smarter solution.

There are limits to this label. It only works on slabs, so vaulted ceilings will still need text for now. It also does not work where a home story includes a split level, as this label can only reference a slabs height to home story or height to project zero.

But if the design has single level floor plans with flat ceilings, this is a smart BIM solution. I will be adding this label to our favorites soon, but it can be used out of the box with a few minor graphic adjustments for prefix/suffix content and pen/fill settings.

Cabinet Objects

This week, Grace has been exploring the use of cabinet objects to represent the doors of a cabinet, allowing a single source for changing the door style and configuration, but leaving the cabinet face and box to a more flexible and detailed modeling element.

Screen Shot 2015-12-10 at 2.23.37 PM

Essentially turning the toe kick and counter portions of the cabinet off. This is a great solution for “future proofing the BIM process“, but requires turning those portions off to achieve the required design and appearance.

You can not set these elements to 0′-0”, as the GDL requires a distance for its script. You can turn the countertop off in the counter edge settings:

Screen Shot 2015-12-10 at 2.24.08 PM


Future Proof Your BIM Process

The WWA BIM Manual home page describes Why, What and When we model design elements in BIM in a somewhat vague and conceptual way. Understanding this concept is incredibly critical though, since designs change throughout the various phases of the process.

We can not get away with not showing elements simply because we don’t know exactly what they are. A BIM process is centered around exploring what elements are and developing them in a circular process. We can take a basic idea or concept and explore massing to detailed iterations in a very fluid way; and if done correctly, we can either start over or go to final documentation with little or no time loss.

Screen Shot 2015-12-03 at 10.59.03 AM

The perfect example of this work flow and level of detail is cabinetry. Cabinet and built-in elements are not only dependent on the phase, but also the design for the best way to model them and when to add the details.

A flush panel euro style cabinet may be best modeled using morphs from the onset. A more shaker style cabinet with overlay panels may be best suited for cabinet objects with preset doors or custom door components. An inset frameless cabinet with recessed panels may be best modeled with walls and doors.

cabinet process

designing from Custom Profile to Morph to Object(s) ensures a seamless workflow and options to “back-track” without starting over

The important thing to note is that the IDEA portion (LOD 100: Basic shape/size), should always be modeled as basically as possible. This ensures that we do not need to know what style or type the element is at first to at least represent that the idea exists. The process to final documentation should be as gradual as possible, even if we need to show higher level of detail than the current phase warrants.

In the style/process example illustrated above, a cabinet type and door style could easily be transitioned to any other design, with little extra time spent on redoing model elements.

This is also one reason that objects (GDL based elements) offer more flexibility than massing or modeling with individual elements, such as morphs, slabs, walls, beams, columns. With GDL doors or cabinets for example, the door style can be changed globally by simply overwriting or replacing the door panel on all cabinets.

To change a door panel or cabinet type on a single morph element or collection of slabs, beams and columns, significant time needs to be invested into revisiting each cabinet elevation and making individual changes to each.