How to use CADMapper to Create Revit Topography

By Jon Henning •  Updated: 10/06/19 •  4 min read

    The intention of this tutorial is to use CADMapper to create a basis for architectural schematic designs. Site information should always be field-verified by professionals in surveying, civil engineering, etc. to ensure accuracy.

    DISCLOSURE:

    CADMapper is a website that can save architects, designers, and planners tons of time by automatically generating 3D information for over 200 cities around the world. CADMapper generates 3D models that can be used with AutoCAD, Sketchup, Rhino, and Illustrator. To generate information for topography, buildings, and streets, CADMapper pulls data from OpenStreetMap.

    Clean up the CADMapper Toposurface file

    STEP 1: OPEN THE CADMAPPER TOPOSURFACE MESH FILE

    In a previous tutorial, I cover my methods for using CADMapper to generate 3D information for site elements and toposurfaces. If you haven’t checked out that tutorial yet, you can find it here: Create a 3D Site Plan Using CADMapper and AutoCAD

    If you are following along with my CADMapper tutorial, you should have your 3D toposurface as a separate AutoCAD .dwg file. Open that file.

    Select the 3D toposurface, and you’ll notice that the geometry is a ‘mesh’. In order to have Revit read this geometry correctly, we will need to explode the mesh. BUT, before we explode the mesh, we should consider an important tool that AutoCAD provides – “Smooth More”.

    STEP 2: Use “Smooth More” to Create a Cleaner Toposurface

    If the surface you are trying to convert is not already a mesh, you can use the commands “CONVTOSURFACE” and “SMOOTHMESHCONVERT” to generate a 3D mesh surface. Select the 3D mesh toposurface.

    Type in command, ‘MESHSMOOTH’ to open the ‘Smooth More’ tool. For CADMapper toposurface files, I suggest using ‘MESHSMOOTHMORE’ 2 times. Any more than twice, and the surface will just have a lot more information, which will ultimately create a larger file and slow down the whole process when we go to import it into Revit. After all, we want to spend our time designing and not waiting for our computers to process massive CAD files.

    STEP 3: Explode the Mesh Surface

    Select the mesh surface and use the command ‘X’ for ‘Explode’. Depending on how many times you chose to “MESHSMOOTH” will determine how many individual grid segments the surface will be exploded into. This is is a crucial step, because Revit will read the vertices of these grid elements to generate the new toposurface.

    Next, save the file as a .DWG.

    Integrate the autocad file with Revit

    STEP 1: Import the .DWG File into Revit

    Open Revit, and create a new file using the ‘Architectural Template’. Under the ‘Insert’ Tab in the Revit ribbon menu, select “Import CAD”. Navigate to the .DWG file you just created in AutoCAD.

    STEP 2: Create the Revit Toposurface

    Once the .DWG file has been imported into Revit, navigate to the “Massing & Site” Tab. Under the “Modify|Edit Surface” menu, select “Create from Import”. Under the dropdown menu, choose “Select Import Instance” and select the toposurface .dwg import in the model space.

    This will generate an additional toposurface on top of the .DWG import. Select both surfaces, and in the center of the .DWG surface, click on the blue pin to unpin the surface.

    Shift-left-click the toposurfaces to deselect the new Revit toposurface, leaving only the .DWG toposurface selected.

    Delete the .DWG toposurface, and now you are left with a clean, native Revit geometry toposurface.

    And there you have it!

    If you found this tutorial helpful, please be sure to let me know on social media — and please let me know what other tutorials you would be interested in me creating. Cheers!

    Continue this tutorial series, here:

    👈 Previous Tutorial: Create a 3D Site Plan Using CADMapper and AutoCAD

    👉 Next Tutorial: 3D AutoCAD Site Linked to Revit Model

    Jon Henning

    Hi, I'm Jon. I write about emerging technology in architecture, engineering and design, and I want to help you push boundaries with the latest tech trends in the AEC industry.

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