What is it

What is Groundhog?

Groundhog is a Free and Open Source SketchUp extension that allows quickly creating Radiance models and performing lighting analysis.

Model it

Create layers, groups, components and materials.

Export it

For advanced analysis or for working on a larger computer

Analyse it

Import your results, or run calculations without ever leaving SketchUp


What can it do?

Layers, groups, components, views, materials, workplanes, illums, windows and more. Groundhog exports your model as you meant it to be.

  • Run Radiance from SketchUp

    Model by Juan Pablo Vasquez, render by IGD

  • Export Groups and Components

    Model and render by IGD

  • Export saved views

    Model by Juan Pablo Vasquez, render by IGD

  • Preview your model without leaving SketchUp

    Model and image by IGD

  • Import results or calculate daylight metrics within SketchUp

    Model and image by IGD

  • Create Radiance Materials within SketchUp

    Model by Juan Pablo Vasquez, render by IGD

  • Difference between Illums, Workplanes and Windows

    Model and render by IGD

  • Comming soon: Electric Lighting

    Model and render by IGD

Who uses it

Who uses it

Hundreds of downloads from all around the world

Get involved

Do you want to contribute?

Groundhog's Source Code, Website and Documentation are all hosted on a GitHub repository. You are welcome to contribute with suggestions, tutorials, logos, icons, documentation, new features or whatever you think is important.

Contribute on GitHub

Add comments on the Wiki, write documentation, let us know of any bugs, ask for new features, clone and add your own code.

Contribute on Twitter

Follow us, spread the word, report bugs, ask for help and tips, ask for new features.

Contribute on Documentation

Publish, fix, enhance and read tutorials in our collaborative documentation.


It is Free and Open Source!

Groundhog is distributed under the GNU General Public License v3 (GPLv3). This means you can use it for anything you want for free. You can also copy, distribute and modify Groundhog as long as you state what has been changed, license the modified version under GPLv3 and make the source code available.

Support and resources

Need answers?

Maybe it has already been answered... Anyway, feel free to ask!

Contact IGD directly

For general questions.

Contact us using Twitter

Does your question fit in 140 characters?

Read the documentation

You can read it and write it.

You can also check the FULL DOCUMENTATION


Start now!

Download the flavour you need or want


Windows x32

Windows x64