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Modelica Buildings library

Build Status

This is the development site for the Modelica Buildings library and its user guide.

Stable releases including all previous releases are available from the main project site at

Instructions for developers are available on the wiki.

Library description

The Modelica Buildings library is a free open-source library with dynamic simulation models for building energy and control systems. The library contains models for

  • HVAC systems,
  • energy storage,
  • controls, including a reference implementation of ASHRAE Standard 231P,
  • heat transfer among rooms and the outside, either
    • natively in Modelica with a detailed or a reduced order model, or
    • integrated run-time coupling with EnergyPlus, aka, Spawn of EnergyPlus
  • multizone airflow, including natural ventilation and contaminant transport,
  • single-zone computational fluid dynamics coupled to heat transfer and HVAC systems,
  • data-driven load prediction for demand response applications, and
  • electrical DC and AC systems with two- or three-phases that can be balanced and unbalanced.

The main project site is

Current release

Download Buildings Library 9.0.0 (2022-05-31)


The Modelica Buildings Library is available under a 3-clause BSD-license. See Modelica Buildings Library license.

Python modules are available under a 3-clause BSD-license. See BuildingsPy license.

Development and contribution

You may report any issues with using the Issues button.

Contributions in the form of Pull Requests are always welcome. Prior to issuing a pull request, make sure your code follows the style guide and coding conventions.

Building binaries

The distribution at contains all binaries.

Developers may build the binaries as follows.

Spawn of EnergyPlus

The Buildings library already contains the compiled binaries that are needed to link to EnergyPlus.

To rebuild the Spawn of EnergyPlus binaries, CMake is required. The binaries consist of the fmi-library, and a library that connects Modelica to EnergyPlus.

To build the fmi-library, which is only needed if is updated, run

cd Buildings/Resources/src/fmi-library
rm -rf build && mkdir build && \
  cd build && cmake .. && cmake --build . && \
  cd .. && rm -rf build

To build the Modelica to EnergyPlus library, run

cd modelica-buildings
rm -rf build && mkdir build && cd build && \
  cmake ../ && cmake --build . --target install && \
  cd .. && rm -rf build

To install the EnergyPlus binaries for the Spawn interface for the current operating system, run

Buildings/Resources/src/ThermalZones/ --binaries-for-os-only

To install the binaries for all operating systems, omit the flag --binaries-for-os-only


To cite the library, use

Michael Wetter, Wangda Zuo, Thierry S. Nouidui and Xiufeng Pang. Modelica Buildings library. Journal of Building Performance Simulation, 7(4):253-270, 2014.

  author  =  {Michael Wetter and Wangda Zuo and Thierry S. Nouidui and Xiufeng Pang},
  title   =  {Modelica {Buildings} library},
  journal =  {Journal of Building Performance Simulation},
  volume  =  {7},
  number  =  {4},
  pages   =  {253--270},
  year    =  {2014},
  doi     =  {10.1080/19401493.2013.765506},
  url     = ""