DesignBuilder Scripting

Customise EnergyPlus simulations through EMS scripts
Customise EnergyPlus simulations through EMS scripts
Range of productivity tools simplify the scripting-writing process

DesignBuilder Scripting tools unlock almost unlimited flexibility in EnergyPlus simulations by allowing you to customise the behaviour of the HVAC equipment, controls and facades.

Key features

The integrated Energy Management System (EMS) scripting environment provides lists of all of the required sensors, actuators, variables, outputs etc in easy to use dialogs. This makes the script writing process straightforward and accessible to any energy modeller with a little coding knowledge. The EMS scripts you write are included in the EnergyPlus IDF input file and execute very quickly at runtime. DesignBuilder Scripting productivity features include:

  • A range of DesignBuilder extensions to the standard EMS syntax allow fully portable scripts to be written. This means that a script written for one project can be used on other projects or even shared with other users on the public script repository.
  • Read building, zone or surface settings from the DesignBuilder model to populate data within the script.
  • Load fully formed actuator, sensor, variable, output statements from easy to use dialogs.
  • Colour syntax highlighting in the scripting window helps with readability.

You can find more information about EMS scripting in the online help.

For more adventurous modellers, the FMU/FMI interface allows you to develop advanced co-simulation applications using C++. Applications for FMU include linking occupant behaviour models or CFD simulations with EnergyPlus.


Some example EMS scripting applications include:

  • Precision control over simulated behaviour for HVAC, natural ventilation, glazing and lighting systems. E.g. you can use EMS to add manufacturer control logic to equipment such as heat pumps or override default EnergyPlus control linkage between economisers and heat recovery.
  • Custom shading controls to model advanced facade systems such as multi-state electrochromic and thermochromic glazing.
  • Linking one system with another (e.g. link earth tube or solar preheat zone to HVAC inlet).
  • Advanced control of natural ventilation actuators based on CO2 or moisture levels within the building.
  • Create your own custom outputs not normally provided by EnergyPlus (e.g. CIBSE TM52 outputs).
  • Dialogs list 1000s of standard built-in EnergyPlus outputs for selection.
  • Researching new building systems or the impact of non-standard occupant behaviour patterns.

EMS is ideal for researchers and more advanced modellers looking to assess the performance of innovative systems that have not yet found their way into the standard list of EnergyPlus capabilities.


Scripting is included in the Engineering Plus and Engineering Pro packages.


The Scripting module also requires the Simulation module.