"Modify Sub Elements" for Ceilings: Why Not, Revit?

[randall_morgan]

Frustration with Revit's Ceiling Modeling Limitations

I'm reaching out to vent and hopefully get some answers about a frustrating limitation I've encountered in Revit. Why is the "Modify Sub Elements" feature available for roofs and floors, but not for ceilings? This restriction is causing significant issues in my current project.

The Situation
I'm modeling existing structures based on point cloud data. One of the buildings has a complex sloping ceiling that would be much easier to model using the "Modify Sub Elements" feature. This would allow me to snap points precisely where I need them.

The Problem
Instead of having access to this intuitive tool, Revit forces the use of the slope tool for ceilings. This approach is far less intuitive and makes the modeling process unnecessarily complicated and time-consuming.

Questions
1. What's the justification for Revit only allowing "Modify Sub Elements" for roofs and floors, but not ceilings?
2. Is there a workaround? Can you use "Modify Sub Elements" in a model-in-place component that's categorized as a ceiling?

The Bigger Picture
This limitation feels arbitrary and goes against Revit's goal of streamlining the modeling process. It's frustrating when software restricts how we can model, especially when dealing with complex, real-world structures that don't always conform to simple tools.

I'm curious if others have encountered this issue and how they've dealt with it. Any insights, workarounds, or even solidarity in frustration would be appreciated!

[vitorbortoncello]

Revit restricts "Modify Sub Elements" to roofs, toposolids and floors because ceilings are treated differently in design. They interact more with components like lighting and HVAC and are often considered architectural finishes, not structural elements, which may explain the lack of similar manipulation tools.

[randall_morgan]

Thank you for your insight. I understand the reasoning behind treating ceilings differently due to their interaction with lighting, HVAC, and their role as architectural finishes rather than structural elements.

However, I'd argue that this distinction, while valid in many cases, doesn't always hold true in practice, especially when modeling existing structures. In my current project, I'm dealing with a complex sloping ceiling that's integral to the building's structure and doesn't interact with typical ceiling-mounted elements.

Moreover, even in standard designs, ceilings can have complex geometries that would benefit from more flexible modeling tools. The ability to precisely control sub-elements could actually improve coordination with lighting and HVAC components in intricate designs.

While I appreciate Revit's attempt to streamline workflows by categorizing elements, I believe this approach sometimes limits our ability to accurately model real-world conditions. Perhaps a solution could be to offer an advanced mode or toggle that allows for more detailed manipulation of ceiling elements when needed, without changing the default behavior for typical projects.

Do you think there's merit to this idea? Or are there workarounds within the current system that I might be overlooking?

[ToanDN]

You can always model a ceiling using roof tool and modify sub-elements of the roof.

[vitorbortoncello]

If you need greater control over geometry, you can use other tools like roofs or floors, although their categories can't be changed to ceilings. In-place modeling is another option, but I generally avoid it due to its limitations in reusability and parameterization and might cause information error when sharing files (Open BIM)

I completely agree with your point about Revit’s categorization. While it aims to streamline workflows, it sometimes restricts our ability to model real-world conditions with full accuracy.

[randall_morgan]

You're right, and that's actually the solution I ended up using - modeling the ceiling using the roof tool to access the "Modify Sub-Elements" feature.

While this workaround does solve the immediate modeling issue, it highlights a deeper problem with Revit's approach:

Categorization Matters: Revit's power comes from its robust family and category system. Using a roof to model a ceiling undermines this system. It can lead to issues with:

-Schedules and quantity takeoffs
-Visibility/graphics controls
-Filtering in views
-Correct representation in BIM coordination

Workflow Disruption: Having to think, "Should I model this ceiling as a roof?" adds unnecessary complexity to the design process. It's counterintuitive and could lead to confusion, especially in collaborative environments.

Data Integrity: In a data-driven BIM world, having elements correctly categorized is crucial. Using roofs as ceilings could cause problems with data extraction, analysis, and interoperability with other software.

Feature Disparity: This workaround highlights an arbitrary feature disparity between different element types in Revit. If the functionality exists for roofs, why not extend it to ceilings?

While I appreciate the workaround, I believe it's important to push for software improvements that align with proper BIM practices rather than accepting workarounds that compromise data integrity and workflow efficiency.

[ToanDN · Accepted solution]

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@randall_morgan wrote:

Categorization Matters: Revit's power comes from its robust family and category system. Using a roof to model a ceiling undermines this system. It can lead to issues with:

-Schedules and quantity takeoffs
-Visibility/graphics controls
-Filtering in views
-Correct representation in BIM coordination

Categories are just one means to classify components.  There are also Assembly Codes or Unicode that can be utilized for this very purpose.

Workflow Disruption: Having to think, "Should I model this ceiling as a roof?" adds unnecessary complexity to the design process. It's counterintuitive and could lead to confusion, especially in collaborative environments.

It is not a disruption, but a workflow planning.  It is recommended for every activity, includes non work related ones.

Data Integrity: In a data-driven BIM world, having elements correctly categorized is crucial. Using roofs as ceilings could cause problems with data extraction, analysis, and interoperability with other software.

This is the same concern as the first one.  So, the answer is the same.

Feature Disparity: This workaround highlights an arbitrary feature disparity between different element types in Revit. If the functionality exists for roofs, why not extend it to ceilings?

Legit question.

While I appreciate the workaround, I believe it's important to push for software improvements that align with proper BIM practices rather than accepting workarounds that compromise data integrity and workflow efficiency.

In the long run, yes.  But I rather be using a workaround than sit tight waiting for a feature to arrive in several years, if at all.

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After all, everything in Revit is a tool in a toolbox.  You can choose to use them for what their name suggest, or you can choose to use them for what they can do.