Put your model
to work.

Give Flux the modelling task.
Keep the engineering judgement.

Try for free
Duplex energy model in the 3D viewer, alongside its thermal zone tree
YOUR MODEL. IN PLAIN SIGHT.Actual workspace · sample duplex

Less clicking.
More questioning.

01

Give it the task.

Ask the agent to inspect the model, edit inputs, or write Python against your project files.

“List every construction and its U-value.”
02

Stay close to the detail.

Explore the geometry, inspect the objects, and review proposed file changes.

“Show me what changed.”
03

Follow the evidence.

Run EnergyPlus, query the outputs, and compare saved runs in the same workspace.

“Compare cooling energy with the baseline.”

Know your tools.

Flux, OpenStudio, IESVE and DesignBuilder workflow comparison
The essentialsDesignBuilder
PricingComing soonFree · open sourceCustom quoteFrom US$1,800 / user / year*
Simulation engineEnergyPlusEnergyPlusAPACHEEnergyPlus
Working interfaceAgent + model workspaceModel editor + MeasuresIntegrated analysis appsVisual modelling modules
AutomationAgent tools + PythonMeasures, SDK + CLIPython API + workflowsPython, C# + EMS
Compare alternativesQuery and compare saved runsMeasures + PATParametric simulationParametrics + optimisation
Sources & scope September 2026

Workflow comparison, not a compliance or accuracy benchmark. Commercial features depend on modules and licences. OpenStudio covers the Application and the SDK / PAT ecosystem; IESVE uses its own APACHE engine.

*DesignBuilder Engineering Fundamentals, single-user annual licence. Engineering packages range from US$1,800–4,650 per year; optimisation and scripting are included from Engineering Plus (US$3,075/year). USD list prices apply outside the UK/EU, before taxes and bank charges. OpenStudio’s free licence excludes optional third-party services. Flux pricing is not yet announced.

OpenStudio ↗PAT ↗IESVE ↗IESVE quotes ↗DesignBuilder 2026 pricing ↗DesignBuilder scripting ↗Optimisation ↗
Other tools in the landscape

Honeybee and Pollination bring energy and daylight analysis to parametric design workflows. IDA ICE focuses on energy, HVAC and indoor climate with its own simulation engine. eQUEST provides a DOE-2-based modelling and efficiency-analysis workflow.

Start with
a what if.

Bring a model. See what Flux can do.

Free to try.

  • Explore your model
  • Work with the agent
  • Run EnergyPlus and inspect results
Try for free

Paid plans coming soon.

Your next
what if.

Open Flux