What's new in v5



DesignBuilder v5 adds a substantial set of new features and improvements compared with v4 including significant productivity improvements for LEED and ASHRAE 90.1 PRM work and a new Scripting toolset to allow EnergyPlus simulations to be customised.  

Other highlights include Combined Heat and Moisture Simulation, new Cost Modelling tools and a Fluid to Fluid heat exchanger component which opens the door to modelling a wide range of new HVAC systems.

To find out about upgrading to v5 see our Upgrade page.

The list below summarises the main improvements. 

3-D Modeller

  • gbXML export provides full 2 way interoperability with other modelling tools (v5.2).
  • Improved gbXML BIM import now fully supports courtyard voids.

EnergyPlus Simulation

  • EnergyPlus v8.5 with further significant speed improvements and fixes.
  • Combined Heat and Moisture Simulation using HAMT or EMPD algorithms
  • Improvements to the link to the JESS online simulation service providing fast cloud simulations through the Simulation Manager.
  • Ground domains allow 3D heat loss to the ground to be simulated with options for basements and slabs.
  • Exterior surface baffle with natural ventilated cavity
  • IGDB window panes database updated to v46. (v5.2)


EMS Scripting tools allow the behaviour of HVAC equipment, controls and facades to be customised. Productivity features include:

  • A range of DesignBuilder extensions to the standard EnergyPlus EMS syntax allow fully portable scripts to be written. Scripts written for one project can be used on other projects and shared through the public script repository.
  • Load fully formed actuator, sensor, variable, output statements from easy to use dialogs.
  • Read building, zone or surface settings from the DesignBuilder model to populate data within the script.
  • Colour syntax highlighting in the scripting window helps readability.
  • Parametric variables linked to optimisation allow EMS settings to be optimised to best meet design objectives. (v5.2)

FMU/FMI interface for co-simulation with external applications. Applications for FMU include linking occupant behaviour models or CFD simulations with EnergyPlus.

LEED and ASHRAE 90.1

A range of new tools to help assess buildings through the ASHRAE 90.1 Appendix G 2007 and 2010 Performance Rating Method:

  • Automatic baseline building generation with proposed and baseline buildings both included in the same model.
  • Guided semi-automatic baseline HVAC system generation wizard.
  • Automatic parallel simulation of the 4 rotated baseline buildings and averaging of the results.
  • On screen comparison of proposed and baseline building simulation results.
  • All constructions, materials, glazing systems, activities, lighting and HVAC systems required for ASHRAE 90.1 2007 and 2010 are included and automatically set based on the climate zone within the DesignBuilder modeller.
  • LEED EAc1, EAp2, Table 1.4 and Energy Star documentation (v5.2).


  • Fluid to Fluid Heat Exchanger Fluid to fluid heat exchanger allows heat to be exchanged between plant/condenser loops.
  • Zone water-to-air heat pumps.
  • Waterside economisers.

LZC and Renewables

  • Building integrated photovoltaic (BIPV) generation for all wall, roof and glazed surfaces.
  • SageGlass electrochromic glazing with a range of control options (v5.2)


  • New Custom IDF variable type allows EMS settings to be optimised to meet design objectives (v5.2).
  • New tool applies optimal design properties to the base building design.
  • New UNIFORMAT II and NRM1 cost KPIs for setting project financial objectives and constraints (v5.2).


  • Major overhaul of the Construction cost modelling calculations with new options to support the NRM1 and UNIFORMAT II standards (v5.2).

Italian Law Links

  • Links to MasterClima 11300 for Italian Law calculations. For more details please contact SGM, our Italian reseller.


Find out about Upgrading to v5.


Download v5.0


The DesignBuilder development team is working on finalising and testing the features listed for the v5.2 release. V5.2 will be made available as a version update for all v5 licence holders when it is released.