How to Rough Out a Site in SketchUp

By Aidan Chopra

Perhaps you want to model a smallish chunk of nonflat terrain that surrounds a building model in SketchUp. Maybe you’re trying to reproduce existing site conditions, or maybe you’re in the process of designing the landscape for a project. There’s a neat technique for cases like this one: You can use From Contours to quickly generate a surface from just a few simple outlines.

Follow these steps to model a simple terrain surface with the From Contours tool:

  1. Extend the bottom of your building down so the exterior walls drop below ground level.

  2. Make your building into a group.

  3. Use the Tape Measure and Line tools to draw the outline of the chunk of terrain you want to model around the building.

    Keep in mind that the resulting horizontal face is flat; just pretend you’re drawing in 2D space. It doesn’t matter if the outline you draw is below, above, or in line with the building, as you see in the next step.

    image0.jpg

  4. Use the Push/Pull tool to extrude the face you drew in Step 3 into a box that extends above and below your building, and then delete the top and bottom faces of the box you just drew.

  5. Paint the walls of your box with a translucent material.

    You can find some in the Translucent library, in the Materials dialog box.

  6. Draw edges on the sides of the box that represent where the ground should intersect them.

  7. Draw edges on the sides of the building that represent where the ground meets the building.

  8. Delete the box you created in Step 4, leaving only the edges you drew in Step 6.

  9. Select all the edges you drew in Steps 6 and 7.

  10. Choose Draw→Sandbox→From Contours from the menu bar to generate a surface based on the edges you selected in the preceding step.

At this point, you need to use the Flip Edge tool and the Eraser to clean up your terrain model — particularly where your building is supposed to go.