Creating 3D home from Civil 3D


I’m new to SketchUp Pro 2018, and I’m trying to make a 3D model of a site for my landscape design project. I successfully imported TIN and have a great landscape, but now I’m trying to complete the homes for the site. I built them in Civil3D in the modeling section, and successfully imported them into Sketchup and placed on my landscape, but they are just linework entities. I can’t figure out how to make solid surfaces out of the line work. Just so I’m clear, I used the front, left and right sides, and rear to create the homes, and the roof is still open as well, so I need pointers on how to connect lines to close up/create the roof. Do I need a ruby console or anything? I wasn’t able to upload my model because it’s too big, but I am uploading a screenshot of one of the homes so you can see how it appears currently.

Any and all advice greatly appreciated. I will check back on Tuesday.


What format was the file you imported into SketchUp?


drawing a line onto an existing line will usually make a face (assuming all other coplanar edges are connected.)
There is also a “make face” plugin that does a quicker job of this if there are lots of faces to create.
If you can you should try to isolate each wall as a group so that they are independent entities and their geometries will not mix together.


For working off imported 2D CAD linework, I’ve ended up adopting a strategy of only using them for tracing guides more often than not. SketchUp can reference all the end points and midpoints as you trace over all new geometry.

  • The imported line work may bring a bunch of layer information that’s at least unwanted, and often violates the consensus opinion of SketchUp Sages here that loose geometry should not be on anything but Layer0.

  • The loose geometry might not be grouped/nested optimally for the shapes you want to create.

  • Be prepared for errors between 2D drawings. The various elevations, for example, might not agree on the height of the roof ridge. Turning the imported lines into faces and then trying to connect the dots can drive you mad when things you think should be planar aren’t.

  • It’s a bit brain challenging sometimes tumbling around these wireframes around and seeing just what you want to see, so it’s good to hide the ones you don’t need at the moment.


The Sages often direct a questioner to the Knowledge Base page that would supplement an answer.
Trimble employees write the Documentation. Sages only write their opinions.

Interestingly, neither SU6 nor SU7 PDF User’s Guides state raw geometry should always remain Layer0.
That changed when Google pushed the documentation online and abandoned publishing a PDF version.

Here’s a link to the last version of SU Help published in PDF format.
SketchUp7 Help

I found this familiar old Help page from 2007 on the WayBack Machine.
Does SketchUp support layers?

The current Help page
Controlling Visibility with Layers — SketchUp Help


I don’t know especially about Civil3D, but many of these AutoCad extensions create their own proprietary 3D objects that other applications don’t understand. You might have better luck if you used the “Export to AutoCad” function or its equivalent in Civil3D to export to a DWG file that might be more compatible with SketchUp.


I imported the file as a 2007 dwg. When I tried to import as a 2007 dxf all sides came in at coordinates very far apart in the SU model.


thanks for the reply. Are you suggesting I trace my existing linework imported from Civil 3D to make faces? Also, do you have the plugin link that you use to “make face”?


the linework I show in my jpg I attached is linework that was exported from Civil3D as a 2007 dwg. I then imported that info SU. I tried exporting to a dxf, then importing into SU, but the linework came in on coordinates very far apart in SU.


Thank you very much for this clear reply. Do you have any plug in suggestions that might make the job go a bit quicker?


In your extension wharehouse dropdown, search “make face” you will see this “S4U Make Face”.