Best IES Alternative for HVAC System Software
IES vs Hysopt
IES is trusted for static building energy modelling — helping you calculate heating and cooling loads and check compliance. But buildings don’t perform on paper alone. Hysopt takes you further with dynamic system simulation, hydraulic design, and control strategy validation — so you deliver HVAC systems that actually work as designed.
What’s the Difference between IES and Hysopt?
IES is a go-to tool for architects and engineers who need static building simulation, thermal loads, daylighting and compliance modelling. It’s excellent for predicting a building’s theoretical energy demand.
But here’s the thing:
IES does not design or verify the real HVAC system that must deliver those results day to day.
Hysopt fills that gap with dynamic system simulation. It turns static load data into real-world system design — balancing hydraulics, testing controls and delivering verified comfort and energy savings.
- Included
- Core feature
- Full thermal, hydraulic & controls
- Not available
- Detailed system design
- Not included
- Built-in
- Not included
- Proven savings
- Static estimate only
- Verified sizing, balancing, performance
- Static building model outputs
Why HVAC Engineers Choose Hysopt
1. Beyond Building Loads
IES estimates how a building should perform. Hysopt shows how the HVAC system will perform in real operation.
2. Find Hidden Problems Early
Hysopt’s dynamic simulation catches oversizing, flow issues and control errors that static models can’t.
3. Deliver Real Savings
With Hysopt’s verified outputs and clear reports, engineers can prove how designs cut costs and CO₂ emissions for clients.
Who Benefits from Switching to Hysopt
MEP Consultants
Take static building loads from IES and design dynamic, optimised HVAC systems.
Commissioning & Operations Teams
Start up systems with fewer issues, no costly balancing fixes and proven control logic.
Energy & Sustainability Managers
Verify that the performance on paper becomes real-world savings.
How to Switch from IES to Hysopt
Switching from IES’s static building modelling to Hysopt’s dynamic system design is easy and powerful — giving you a complete workflow from loads to real performance:
• Use IES load results as reliable input data
• Build dynamic hydraulic and thermal simulations in Hysopt
• Balance flows, test control strategies and size equipment properly
• Get onboarding help, templates and expert support to make switching simple
- Full simulation engine
- Static loads only
- Validated and testable
- Not available
- Built-in
- Not included
- CO₂, cost, energy
- Theoretical only
Frequently asked questions
Does Hysopt replace IES for load modelling?
Is it easy to switch from IES to Hysopt?
Can Hysopt simulate the whole HVAC system?
How does Hysopt help reduce energy use compared to IES alone?
Ready to see the Difference?
Make the switch from IES to Hysopt today — and prove your HVAC system works in practice with Hysopt’s dynamic simulation, hydraulic design and verified savings.
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