Indoor Environmental Quality (IEQ)
The EPFL contribution to INPERSO focuses on the development and application of a performance-based Indoor Environmental Quality (IEQ) benchmarking and decision-support framework, combined with a sensor-driven recommendation system to support healthier and more comfortable indoor environments in residential and educational buildings.

At the core of this work is ATLAS, a novel IEQ index that integrates four key IEQ domains—Indoor Air Quality (IAQ), Thermal Comfort, Lighting, and Acoustics—using data from validated low-cost sensors and occupant feedback surveys. Unlike traditional single-parameter approaches, ATLAS provides a holistic, scalable, and user-oriented assessment of IEQ, enabling meaningful comparisons across buildings and over time.

The framework is designed to evaluate IEQ before, during, and after renovation, supporting evidence-based assessment of renovation impacts on occupant comfort and well-being. In parallel, EPFL is developing a personalized recommendation system that translates real-time sensor data and IEQ index outputs into actionable guidance for occupants and building operators via in-space interfaces (e.g. tablets). Together, these technologies support informed behavioral and technical interventions, bridging the gap between sensing, interpretation, and action.

Objectives

Develop a robust and scalable methodology for benchmarking IEQ in residential buildings within INPERSO

Enable sensor-driven, personalized recommendations to guide occupant behavior and technical interventions

Create a novel integrated IEQ index (ATLAS) combining physical measurements and occupant feedback

Quantify the impact of recommended interventions on overall IEQ performance

Demonstrate how building renovation affects IEQ, comfort, and well-being

Replicate and validate the IEQ benchmarking tool in three Swiss schools

Work Carried Out So Far & Milestones Achieved

    • Integrated four IEQ components (IAQ, thermal comfort, lighting, acoustics)

    • Combines low-cost sensor data with occupant survey feedback

    • Designed as a performance-based benchmarking tool

    • Validated low-cost measurement methods deployed

    • IEQ data collected in three residential demonstration buildings

    • IEQ surveys designed, collected, and incorporated into the ATLAS framework

Remaining Work

Apply the ATLAS IEQ index pre-, during, and post-renovation in selected INPERSO buildings

Contribute results to INPERSO dissemination, website content, and cross-partner analyses

Conduct replication studies in three Swiss schools to test robustness and scalability

Deploy and test the personalized recommendation system, including:

Integration of real-time sensor data

Tablet-based user interfaces for occupants

Behavioral guidance and technical recommendations

Quantify the IEQ improvements resulting from proposed interventions

Expected Impact 

    • A validated, transferable IEQ benchmarking methodology suitable for large-scale deployment

    • Demonstration of the added value of low-cost sensing combined with occupant feedback

    • Improved occupant comfort, well-being, and awareness of indoor environmental conditions

    • Empowerment of occupants through clear, actionable recommendations

    • Strengthened credibility of INPERSO as a project delivering measurable IEQ outcomes

    • Support for renovation strategies that improve IEQ while avoiding unnecessary energy penalties

    • Evidence-based decision-making for healthier indoor environments