Paper House Project: Part 2 – Edit Texture Images

Part 1 of this series showed how to use the Flatten and Unwrap extension to make a simple paper house in SketchUp. In that project, your kids (or you) print on blank paper and use markers or crayons to add windows, doors, materials, etc.

This project shows a different method: painting materials in SketchUp. I started by adding some basic materials to my blank house.

Set Your Graphic Editor

Here’s the issue with the Flatten extension and objects like windows and doors. If you add a rectangle inside a wall, to represent a window, the unfolding won’t always work correctly. That window rectangle might be cut out, or might not be painted correctly. (The extension was made for unfolding or unrolling entire faces, such as for CNC milling or laser cutting. Not for little paper houses.)

I even tried adding a window and hiding its edges, to make SketchUp think it wasn’t a separate face. Didn’t work.

So all faces must remain whole. Which means that any windows, doors, etc, that you add must be part of a face’s material.

I came up with two ways to get this done. This post shows how to use the Edit Texture tool to add details in a graphic editor. Parts 3 and 4 show how to use Photo Match.

For this method, you’ll need to have a graphic editor like Photoshop. I used Paint Shop Pro, and there are free editors like Gimp. (I really like Inkscape, but that program doesn’t let you save a JPG, which is the format for most of SketchUp’s texture images.)

Whatever graphic editor you choose must be set to work from within SketchUp. This is done in SketchUp’s Preferences window, Applications page.


Add Windows and Doors

We don’t want to edit the materials themselves, we want to edit the material of each face. It’s easier than it sounds. Choose one of the faces that gets a window or door, and right-click on it. Choose Make Unique Texture.



This creates a new material in the “In-Model” collection of the Materials or Colors window. (Click the House icon to get to this collection.) This new material has the same shape as the face you clicked. Find this new material (mine is the first one in the list below), right-click on it and choose Edit Texture Image. On the Mac, right-click on the face in the model and choose Texture / Edit Texture Image (this works for PC too).


This opens the texture image in your editor. I used the basic drawing tools to add a door and window.


Here’s the important thing: when you’re finished editing, the image must be saved in the same location (some hard-to-identify folder) and with the same format (usually JPG). The easiest way is to just close and save. If you’re asked to merge or flatten layers, or overwrite the original texture image, say yes.

As soon as the image is saved, the edited material appears in SketchUp.



I went ahead to the other faces and edited those images the same way.

Flatten and Print

Here’s the best result I got from the Flatten extension:
And here it is after one of my kids folded and taped:


Next up, in Part 3 – how to paint a house using Photo Match.


About Bonnie Roskes

Bonnie Roskes has been writing tutorial-style projects on 3D modeling software, primarily SketchUp, since 2001. Her website, offers a wide variety of learning materials for all ages, from kids in grade school through design professionals. Her materials cover general 3D design, 3D printing, geometry, interior design, geo-modeling, and more, and future books are in the works. Read more about Bonnie.