SIM-VICUS is hosted on github, where you can download the source code, post feature requests and bug reports. This page also includes all model and developer documentation:




Energiewende Bauen Release

Some new features including:

  • Enhanced boundary conditions view with option to check outer boundary conditions
  • Auto-save function: the project will be saved automatically in a custom time interval (default 10 min). In case of a crash, a recovery option is available
  • much clearer naming of dialogs and widgets in german translation

Moreover, lots of bugfixes have been implemented:

  • bugfix clipping algorithm
  • bugfix rubberband selection
  • performance improvement in interlinked table widget


building training session release

In preparation for the upcoming workshop for building simulation, we have done even more bug fixes and lots of convenience enhancements, including:

  • enhanced database dialogs, with filter function and legend
  • bugfix smart clipping algorithm
  • more robust face normal calculation
  • long wave radiation model inside rooms: inner wall surfaces can exchange long wave radiation now

SIM-VICUS 1.0.1 Release

Several bugfixes and additional translations after our major Release 1.0

SIM-VICUS v1.0.0

Version 1.0.0

We have put a lot of work in the last months - now it is done - SIM-VICUS version 1.0.0 is available. The most important new features are...

  • Smart Clipping Algorithm: Rooms with different geometries can be automatically clipped and thermally connected. This makes the creation of complex building models much easier. IFC Import: IFC files can be imported directly into SIM-VICUS, which significantly shortens manual processing.
  • geoJSON import and export: For networks, geoJSON files can be imported and exported with corresponding attributes (pipe diameter, connection power).
  • Live result display: Simulation results can be displayed in color directly in SIM-VICUS. The buildings/networks are colored live and time-dependent by interpolated colormaps.
  • Shading calculation: The shading calculation has been revised and in addition to the classic ray tracing there is now the possibility to pre-calculate shading factors by means of area clipping. This makes the pre-calculation even faster!
  • New design: All building and mesh properties are now even more clearly accessible.
  • Numerous other bug fixes and minor improvements

v0.9.1-beta Bugfix Release

Several bugfixes have been done.

  • crash in surface connection table widget fixed
  • copy structure fixed for buildings
  • corrected german translation

v0.9.0-beta - BauSIM Release

Lots of new features and bugfixes have been implemented until the last minute of BauSIM 2022, preparing SIM-VICUS for the according Workshop. Main changes include:

  • new structuring of add / edit geometry and parametrization modes, including new icons
  • revised database dialogs, including many plots for enhanced usability
  • new feature: thermo-hydraulic networks can now created, edited and parametrized, making it usable for everyone
  • added demo examples for buildings and networks: you find them on the welcoming screen -> demo casees
  • many validation cases for NANDRAD solvers have been conducted within the SimQuality test suite (see
  • updated the entire german translation, all dialogs should now be usable in both english and german

We hope you enjoy the new version and that our nightly sessions have lead to a successfull release!

Screensh2 Screensh1

Note: Linux release requires installed qt5 libraries and recent gcc libs (was built on Ubuntu 22.04 LTS). Debian deb packages follows in release PPA.

v0.8.0-beta - Towards real-life projects

Since the last release before Christmas we have done quite some changes to the software. While the NANDRAD solver itself is already quite mature, we put a lot of effort into the user interface, specifically geometric editing. While the IFC-Import plugin is getting closer to the first release, we need more modeling capabilities in the user interface. In the process, we re-arranged the various add and edit functions and created a vertical toolbar as separator between property windows and modeling area:


Now translation, rotation and scaling works reliably, even for arbitrary oriented local coordinate systems. We also made the transformation edit operations a two-stage process: first, a preview of the resulting transformation is shown, and you may then apply or reject these changes.

The german translation is included, but will be extended in the next days (until release 0.8.1), so that most of the UI are now fully available in German.

There has been some work towards hydraulic network modeling as well, yet, this part of the software is still considered highly alpha stage.

v0.7.1-beta - Bugfix Release

This release fixes a bug that prevented the simulation to be started in version 0.7.0. Also includes several improvements in property widgets. Some features are in the middle of being implemented, so tread carefully ­čÖé

Some notable changes (with tickets):

v0.7.0-beta - Christmas Release

This release features many many small and larger additions.

UPDATE: the release binaries have been updated at Dec 29th to include some bugs that appeared during testing.

Complete overhaul of the database handling

Bildschirmfoto von 2021-12-19 18-04-48

  • colors indicate data source
  • bold font indicates, which database elements are actually being used in the currently loaded project
  • database elements can be built-in, user-database or project-specific; the latter being the new default for newly created database elements; this greatly improves database element handling, since project-related database elements are only shown for respective projects
  • only used database elements are embedded into projects

Pre-computed shading calculation functionality

You can define shading elements around the building/at the facade and then let the user-interface calculate hourly shading percentages for each surface/window.

SIM-VICUS 0 7 0 - shading_calculation

The shading calculation is now done completely in parallel, thus substantially reducing calculation time for larger geometries.

SIM-VICUS 0 7 0 - shading_calculation_in_parallel

Detailed output definition handling

  • default outputs for building and network simulations have been extended and should suffice for many projects
  • there is now also a detailed output grid and output definition editor available, where all outputs native to the NANDRAD model can be individually configured and customized

SIM-VICUS 0 7 0 - output_definitions

Linux Compatibility and Usability Improvements

  • since Ubuntu 20.04 and other derived distros ship a Qt dependent library with missing resources, using the GNOME file and color chooser dialog may crash SIM-VICUS; if this happens, open Preferences->Misc and check Do not use native color/file dialogs!
  • you can now choose to run the external tools (mostly the NANDRAD solver kernal) as background process or via different console applications; mind, that you need to have these terminal programs (XTerm, Gnome-Terminal or Konsole) installed, otherwise you will get an error that NandradSolver cannot be started
  • the Help menu now includes a Linux-only button Help->Desktop integration (Linux) which will create a menu link for SIM-VICUS and register *.vicus file extensions with SIM-VICUS. Simply run this command when starting the application the first time, log out and back in and you should be all set.

Model Enhancements

  • many model features have been improved/added, mostly motivated from actual engineering projects and SimQuality-test case development. See change log and closed issues for details.

v0.6.3-beta - Usability upgrades and many small bug fixes

This release is a consolidation release - we started using SIM-VICUS in some real-world projects and stumbled across quite a few issues that we fixed right away. With the larger models we needed to look at performance a litte and improved the navigation tree a lot (both functionality-wise and regarding performance).

v0 6 3

Look at the closed issues list for details.

v0.6.2-beta - IDF Importing Upgrades

A lot of IDF import projects have been tested and bugs related to different IDF flavours have been fixed. Also, importing of slightly imperfect geometry (polygons with vertexes out of plane; polygons with same vertexes/zero length segments etc.) has been improved.

Also, the NANDRAD FMU Generator tool has received as substantial feature upgrade (sorting/filtering/input variable mapping), that might be particularly useful for larger simulation projects to be turned into FMUs:


Now there is also a manual (though in german) for this tool:

Also, we switched to VC 2019 and Qt 5.15.2 on Windows.

v0.6.1-beta - Fine-tuning for Public Release

This version includes many smaller improvements and fixes, primarily targeting the Windows platform (Linux version works fine; Mac version seems to work fine, too). Also, IDF Import has been further improved - now pretty large models can be imported already:


Release Notes

  • Windows : Windows 7 64bit...Windows 10 64bit; When running installer, Windows first blocks the execution; select "more information" and then install.
  • Linux : Ubuntu 18.04 LTS and newer (and similar distributions), requires installed Qt5 libraries. Run SIM-VICUS in terminal and install missing library dependencies.
  • MacOS: El Capitan (OSX 10.11) and newer; Requires "installation from other sources" being enabled in security settings.