Building Science Software & Consulting

Enabling Better Buildings

Professional-grade simulation software and expert services for architects, engineers, and building scientists worldwide.

Trusted by professionals in 40+ countries

Our Products

Professional-grade building physics simulation tools powered by proven WUFI® technology, now in the cloud

Flagship

METr

Passive building energy modeling for Phius certification and high-performance design

For: Phius certifiers • Passive house designers • Energy consultants

  • Phius 2021 & 2024 certification support
  • Cloud-based — no installation required
  • Based on proven WUFI Passive technology
Most Popular

C3RRO Plus

Dynamic hygrothermal building simulation for energy and moisture analysis

For: Building scientists • Moisture consultants • Forensic analysts

  • Coupled heat & moisture transport
  • Based on proven WUFI Plus technology
  • Cloud-based simulation
For Developers

C3RRO API

Integrate hygrothermal simulation into your applications and workflows

For: Developers • Research teams • Platform builders

  • RESTful API with JSON responses
  • Automate thousands of simulations
  • Python & JavaScript SDKs

The 3 C's — Work With Us

Beyond software — partner with our building science experts for custom solutions, research, and knowledge transfer

Code

Custom software development for building science applications. We build simulation tools, certification platforms, and integrations tailored to your organization's needs.

Discuss Your Project

Compute

High-volume simulation services and research computing. We run complex analyses at scale — from parametric studies to large-scale building stock assessments.

Explore Compute Services

Consult

Expert building science consulting. From forensic moisture investigations to research collaborations, our team brings PhD-level expertise to solve complex problems.

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Our Story

Founded by former Fraunhofer Institute researchers who created the world-renowned WUFI software suite, C3RRO (pronounced "zero") brings decades of building physics research into modern, cloud-powered tools. Our name represents our core services — Coding, Computing, and Consulting — and our mission: enabling buildings with zero energy waste, zero durability issues, and zero compromises on comfort.

Learn more about our team and mission

What Drives Us

We believe that integrating building science know-how in the building design and operation phases can significantly improve occupant health and well-being alongside building quality while enabling buildings to contribute to reduce greenhouse gas emissions.

Better Buildings

Improving health, comfort and sustainability of buildings

Zero Carbon

Fostering environmentally responsible building practices and technologies

Integrity

Cultivating a culture of transparency and honesty in all our actions and decisions

Why Choose C3RRO?

Built by building physicists, for building professionals

Cloud-Based

Access from anywhere, on any device. No installation or updates required.

Proven Technology

Based on WUFI — trusted by thousands of professionals worldwide for decades.

Research-Backed

Developed by former Fraunhofer Institute researchers with PhD-level expertise.

Standards Compliant

ISO 13788, ISO 15026, EN 15026, ASHRAE 160, Phius 2021 certified.

Comprehensive Support

Extensive documentation, video tutorials, and expert technical support.

50+ Years Expertise

Combined team expertise spanning five decades of building physics research and software development.

Ready to get started?

Transform your building projects today

Join leading architects, engineers, and building scientists using C3RRO for sustainable building design.