AutoCAD Civil 3D to Revit

I recently worked with AutoCAD Civil 3D and explored the various possibilities for creating toposurfaces in Revit from Civil 3D objects.

My first impulse was to import the surface as a DWG, and use it to create my toposurface. But a Civil 3D surface object is not identified when imported in Revit.

I use the Extract Object surface function in AutoCAD Civil 3D to transform every surface contour in a 3D polyline.

Extract Contour

Back in Revit, I import my surface as a set of 3D polylines following contours in my AutoCAD Civil Surface.

In the Toposurface tools, I select the imported DWG, and check the layers containing these polylines.


Revit creates a surface point along every surface contour, and rebuilts our surface.

If you are a Subscription customer, you have access to the LandXML import from Site Designer, recently added to Revit. Start by exporting your AutoCAD Civil 3D surface in LandXML.

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Then use the Site Designer to import it back in Revit.


The resulting Revit toposurface contains ten times less points than the version created from contour lines, which can be game-changing, especially if your are dealing with large or complex surfaces.

I didn’t found any free plug-in to import directly LandXML in your Revit model, but if you are of the DIY type, you can use the example of code provided by Jeremy Tammik on his blog.

You can also import AutoCAD Civil 3D points directly in Revit. To do so, you first have to change the style of your surface to display all its points.

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Then, extract these points as simple AutoCAD points and convert them to COGO points. Here, make sure to set the Prompt for Description to Automatic, or you will have to type a description for every one of these point, which can be somehow tedious for thousands of points.

Edit Point Creation oprions

Now, you can export the coordinates of these COGO point as a Comma Separated text file, and use this file to create your toposurface in Revit.


This option is a nice workaround if you don’t have the possibility to import directly LandXML in your Revit model.

Project Review with BIM 360 Glue

We are actively searching for a cloud-based solution for reviewing our models, and products from Autodesk were among the candidates, so I give a try to the Glue platform.

Autodesk BIM 360 Glue is the cloud-based solution for visualizing and reviewing BIM project, based on the DWF format from Autodesk.

I have to check it as a potential solution, so I will share my first thought here.

BIM 360 Glue work with a cloud-based repository, were we access from the web-browser admin page and the local client. As usual, everything is project-oriented.


The admin interface provide every basic tools for administrating your projects.

Creating a project come in a few easy steps, were you name it and select user to be project administrators.

Create Project

After this first step, every project admin can invite new members to the project, and define their permission level.

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Once you have been invited to a project, you will receive a nice invitation to download and install the client. The entire process is well thought, and no user should have any problem to download the client.

This client provide everything you need to review your model, with properties, length and area measures, saved views, sections and markups.

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To upload content to the Glue platform, we use the Revit plugin. Once you are connected with your Autodesk account into Revit, you can upload view and sheet directly from the Revit interface.

Just click the Glue button, select your project and the views you want to upload, and Glue will take care of everything else.


It also check if a given view has already be uploaded, and ask us if we want to update it, or create a new one.

If we update one, a notification appear on the client. Hitting the refresh button give us the latest version.

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The activity panel show us every version of the uploaded view, and allow us to reload any previous version.

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It seems than Autodesk BIM 360 Glue is a really interesting solution for project review. The integration with Revit and the versioning system add great features to an already nice viewer. The only missing thing here is the ability to print directly from the client.

Autodesk Formit and Revit

Autodesk Formit is an example of how far web-based solutions have progressed. Since 3D application need heavy calculation for display, they were generally limited to the heavy client format, until solutions like Autodesk Formit appear.

This 3D sketching tool allow us to quickly create building concept in a web browser or through the mobile app, then further develop this concept in Revit.

Autodesk Formit greets us with a nice introduction screen describing the main functionality.


I generally start by setting up the units to metrics.

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Afterward, everything is quite easy to use, and look pretty much like a web-based Sketchup. Let draw a little sketch of our main plan:

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Extruding this sketch give us the first draft of a building.

We can define levels in our model to calculate gross area for our future building.

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These surfaces are updated as we edit the form of our mass:


Once our model is located, the shadow and Sun and Shadows tool allow us to create a small daylight analysis:


While we work, our model is saved to our Autodesk 360 account, in the Drive section. Along the Formit format .axm, a .rvt file appear. This rvt file is automatically converted from our Formit model to be used in Revit. We can download it to continue our design in Revit :

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The Formit model appear as an In-Place mass in Revit, which can be edited directly in Revit. Each previously defined levels are also integrated in our Revit model, along with corresponding Mass Floors.

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We can enhance our design by using this in place mass to create a Curtain System, some floor and interior divisions. Pretty quickly, we have a fully functional first sketch of our building, with elevation, floor plans and a nice rendering.

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My only regret is to have to use the Revit model provided by the Formit conversion. I think it would be more convenient to retrieve a Revit Mass family to be integrated in the Revit template of our choice. We would lose the levels creation, but gain more flexibility for an early stage workflow.

Revisions and Revision Clouds

To highlight modifications or issues on Revit drawings, Autodesk provide us with one of the oldest change tracking device, the revision cloud, and a set of high tech features to handle it.

The workflow promoted here is to add a handful of revision clouds wherever they are needed, and link these revision clouds with metadata describing the issue.

In Revit, every revision cloud is associated with a revision, as we can see in the Properties panel of our revision cloud.


These revisions are managed in the Sheets Issues/Revisions panel, and can be seen as issues to be addressed.


These revisions are displayed in a revision schedule, a table added to the title block family during its creation.

Every revision cloud visible in a sheet have its associated revision displayed in the revision schedule embedded in the tittle bloc. Here, I had a revision cloud on the sheet, its associated revision appears in the revision schedule of the sheet.

OneRevisionsI can also add a revision cloud directly on the view, its revision will also appear on the revision schedule.

Revision2 These clouds can be hidden on a per revision basis, in the Revision panel. This command will hide every revision cloud associated with the selected revision. However, it does not remove this revision from the revision schedule.


HideRevsion1 This allows us to keep some kind of history for every issue addressed and resolved, along with their revision cloud, without having our views obscured with outdated revision clouds.

The Per project/Per sheet numbering option allows us to define if we manage our revision numbers for the whole project, or on a per sheet basis.


Look at the revision numbers on the following example to understand how this work:



Sadly, Revit does not provided any built-in function for scheduling directly revision clouds, just like we could do with Note Block for annotation symbols. When I need a revision clouds schedule, I use Revit BIMLink from Ideate to export these revision clouds to an Excel datasheet. There is also a free tool from Case Inc. to export cloud data to a CSV file, the Revision Cloud Data Export to Text File, included in Case Revit Add-ins.

Beam Annotations

An article from Line Shape Space drive me to the Beam Annotation tools, and the various possibilities to automatically tag a set of beams.
The first idea when having to annotate a set of element is the Tag All function, quite efficient, but limited only to a tag by category. Furthermore, this function does not have the possibilities to add different tags on the same object.


To annotate efficiently a large set of beams, a specific tool exist, Beams Annotations. It functions pretty much like the Tag All command, but with more options.


You start by selecting the set of beams you want to annotate (All beam or only selected one), and if you want to include linked models elements.
Things become quite interesting with the other part of the windows, which display a schematic beam with six slots:


This second part allow us to describe where we want to place Structural Framing tags or Spot Elevation on our beam.

Here the possibilities are quite extensive. On every six position of each beam (start, middle, and end, on each side), you can select different options to place a Structural Framing Tag or an Spot Elevation to display top and/or bottom elevation for the beam:


To showcase this feature, I create a set of beam, distributed on the same plane:


In just a few click, I place a tag for every beam along with a nice Spot Elevation displaying the bottom elevation of the beam.


This tool become extremely powerful when dealing with slopped beams. To showcase this feature, I create a set of beams aligned along a complex surface. To create quickly this kind of beam system, I use Grasshopper with the Hummingbird plug-in. I describe the complete procedure in one of my older post.


These beams are displayed as a grid in a plan view:


I select the Beam Annotation tool, and add a Spot Elevation at the stating and the ending point of sloped beams, along with a Structural Framing Tag on the middle.


After running the command, Revit add a Structural Framing Tag and two Spot Elevation on every beams in my view:


These annotations place themselves nicely along the beam, and a few adjustments with the setting adjust them perfectly on the view:


From Rhino to Revit

My previous post was describing how I use Grasshopper to modify a complex ceiling surface in Rhino. Once this surface is correctly modeled by taking into account constrains set by the actual construction of the ceiling (space taken by structural framing, planarity, maximal angle …), I have to create construction documentation from it.

I need to produce drawings from the 3D models of the ceiling to make it understandable by someone who will built it.

Revit will be our software of choice here. The power of Revit resides in its ability to efficiently produce drawings from a model. To be able to represent our Rhino surface on 2D drawings, we first have to create a Revit model from the Rhino surface.

After some trials and errors with the DWG export options of Rhino, I ended up exporting my surfaces as an ACIS (.sat) file, with the default Autocad export configuration.


I import this .sat file in a new Conceptual Mass family in Revit. The positioning is set to Origin to Origin to place our ceiling in its correct position regarding the origin of the massing family.


I insert this family in my Revit project, and use two dimensions to place it at the origin of the project.


This massing family allow us to create a curtain system by face, by selecting every face of our mass. I use it to create two curtain system, each one with a specific purpose.


The first one is populated only with curtain panel to represent the finish face of our ceiling. Since every panel fit a face of our massing family, we don’t need to add any subdivision into this grid. Curtain panels are 100 mm thick, and have a 50 mm offset to place their finish face along the surface of the curtain system.

I create another curtain system to model the structural element of our ceiling. This curtain system is populated with specifically designed mullion, and without any curtain panel. These mullions represent the supporting elements of our ceiling, and are modeled along the border line of each panel.


Creating a specific curtain system to model mullions allows a greater control over the elements, and does not interfere with the previously created curtain panels.

Once these panels and structure are modeled, Revit will gladly create any needed section view, with all required graphic styles and tags.


Every element is also fully documented, and therefore schedulable, allowing us to extract information like the surface of every panel, or the length of the structural framing.

I will enjoying my summer break for the next few weeks, and will put BIM 42 on hold. Next post in September!

Drawings in Navisworks

One of the main complain I heard from Navisworks is to only be able to see a 3D view of the model and not the drawings created from it. It is why I use Design Review to review drawings produced within Revit.

On the other hand, Design Review is generally not powerful enough to display large 3D models, and in this case, Navisworks has to be used.

I recently discover a solution for combining the best of these two applications by integrating DWF files in Navisworks.

To showcase this function, I create a new Navisworks model and append a Revit model in it.


To be able to see sheets produced within the Revit model, I export them in a new DWF file from Revit:


This DWF file can be loaded into Navisworks through the Broject Browser menu. Just hit the Import Sheets & Models button to load the content of this DWF file. We can see its sheets displayed in the Project Browser window:


After a right-click -> Prepare All Sheets/Models, we can display these drawings in Navisworks just like in Design Review:


Every element in these views is selectable, and its properties are displayed as well.

An interesting feature is the ability to select an element and display it in another view. Just select the element, right-click and hit Find Item in Other Sheets and Models. Navisworks display every views were we can find the selected element.


This feature present in Revit was missing in Design Review and allows for a quick review of elements from the drawings to the 3D view. On the other hand, some markup tools present in Design Review are not available in Navisworks, and we don’t have the ability to import these markup back in Revit.

Trying out Autodesk 360

I was recently searching for a web-based collaboration platform to quickly exchange models between people from different organizations, and since Autodesk had just release its new flavor of Autodesk 360 website, I gave it a try.

The first impression when logging to the new Autodesk 360 Hub is the integration of social capabilities. Every modification is displayed in a handy timeline for everyone to see. I had some prior experience with the project management tool Basecamp (, and I see in this new version of Autodesk 360 some of the features that made Basecamp so successful.

These features, along with the new domain name (, show the effort of Autodesk for producing a complete web-based solution for reviewing BIM content.
Everything in Autodesk 360 is organized around projects, which come with their own calendars and wikis. To work with Autodesk 360, you first have to create a new project and invite members to this project:


After adding a nice logo to your project, you can create folders and start uploading Revit models:

uploadFilesThe upload is pretty quick, but the file has to be processed to be visible through your browser.


Every members will be able to see and download files uploaded in their project. These model also appear in the timeline for everyone to see or comment them.


Once downloaded and processed, the model become visible in the embedded viewer browser. This is where the main feature of Autodesk 360 lies. The 3D model run smoothly, and the whole experience is nearly the same than with a desktop-base viewer.


Along with showing the 3D model, Autodesk 360 display every sheet embedded in the uploaded Revit model. My only wish here is to be able to annotate the drawing just like we do in Design Review, but I hope this will be available in a future release.


Another nice feature, the 3D viewer allow us to isolate elements by categories and display every elements properties.


It’s still miss the ability to create section, and most of it, to be able to download Revit sheets as pdf for an easier reviewing, but I don’t lost hope.

During my whole experience, I just encounter one problem, with my model freezing in generating preview mode just after downloading it.

On the whole, the new Autodesk 360 come really close to a mature web-based model reviewer, and I see a lot of new applications coming to life, especially for the one who are not spending their days in front of Revit, but still need a quick access to the model.

Revit Performance Tips

A regular complain about Revit is its slowness. If this can be a psycological problem coming from people used to the quick reaction time of AutoCAD, it can also become a real problem when working with large models on short deadlines.

I’m use to separate Revit performance in two parts, opening the model and displaying it:

Displaying complex views

When a view become too complex for Revit to display it properly, zoom and pan actions become too slow to work properly.

The main rule to avoid this is to display only what you need. Close any unnecessary view, create cropped a view to work in a specific area, and hide every useless element.

Some visual styles need more power to run, keeping everything in Wireframe or Hidden Line can be a good practice. Even with these visual styles, filters with solid fill pattern override can slow down your view. Prefer lines override, or better, no override at all.

Link CAD only on a specific view (Current view only), and limit these insertions to the minimum. Having a bunch of DWG files displayed in every view of your model is bad for Revit performance and your spirit.


Loading large models

Another part of the problem lays in the time a model take to open, save and synchronize with its central. This time tends to augment with the size of the Revit file. If the size of a model is not a problem in itself, it can be a symptom of a poorly organized and therefore slow model.

To avoid ending up spending more time watching Revit starting than actually working with it, the main rule is to keep your model tidy.

Start by removing every unused view, family or group. Used wisely, the Purge Unused Element command can be useful here. Don’t use Revit family content sites. These families ae generally stuffed with heavy materials, complex geometries and parameters you don’t need. It’s also a good practice to use families provided by Autodesk with Revit.

Every model should have a starting page, defined in the Manage Project tab.


I generally use a Drafting View to display a handful of information about the opened model.


If someone complains about a model becoming slower to open each time, ask every user to actually count how much time it take to open it. Having quantified feedback about Revit performance while opening large model can be really useful to prevent model for become unusable.

Revit Phases

Phases are a very interesting feature in Revit, allowing us to place our project in time. Phase can also become a major headache when not used properly, so in order to understand it, I wrote a few lines about it.

The first step while working with Phases is to define them, in the Project Phases tab of the Phasing window:


Once these phases are created, a lifespan can be defined for every object in our Revit model. To do so, every building element has two properties, Phase created and Phase Demolished. These two properties define the life of our object, when it is created and when it will be demolished.

To illustrate this, we create a few object and place them on a timeline:

  • Four walls, “created” during the Existing phase and never demolished.
  • A small kitchen, created in Phase 1 and demolished in the same phase.
  • Two columns, “created” during the Existing phase and demolished in Demo phase.
  • Three partitions walls, created in Phase 2 and never demolished.


To place ourselves on this timeline, every view has a Phase parameter. This position in time define how Revit will display elements regarding their life cycle.

To illustrate my explanation, I create a new phase filter, called Phase Highlight, with the following properties:


I also create graphic overrides to change object colors by their phase status:


Every element created in the current phase and not demolished during this phase has the New phase status. For example, if we place ourselves in the Existing phase, the four walls and the columns had just been created, and appear in cyan (New status graphic override):


Every element created during an earlier phase, and not demolished this phase are in the Existing status. If we place ourselves in the Demolition phase, we can see the four wall becoming red (Existing status graphic override):


But if this element is demolished during this phase, and has been created on an earlier phase, it had the Demolished status, like the two columns in this example.

If the element is created and demolished in the current phase, it take the Temporary status, like the kitchen in this example (Blue is the Temporary Status override):


Since elements are displayed only if they are actually present during the current phase, we have to place ourselves in the Phase 2 to be able to see the partitioning walls:


If an element is not fitting in any of the four Phase Status, it is not displayed at all, meaning that we cannot display an element that appear in a future phase.