EPBD: Energy-Efficient Buildings Need Healthy Indoor Air

Did you know that buildings consume around 40% of all energy in use today? At the same time, they generate nearly 35% of greenhouse gas emissions. That is why the new version of the Energy Performance of Buildings Directive (EPBD) has become one of the most critical documents in European energy policy. Its goal is not only to reduce energy consumption but also to ensure healthy indoor air and a stable indoor environment for more than 450 million EU citizens.

What kind of indoor environment do buildings provide for the people who live and work in them?

Europe no longer asks “How much energy does a building use?” but instead focuses on a far more essential question: What kind of health conditions does a building create for its occupants?

Experts across Europe have been warning for years that healthy indoor air is a fundamental prerequisite for quality of life, productivity, and long-term health. This message stood at the center of the webinar “EPBD Unpacked – Why indoor climate and energy efficiency must be addressed together.”

The technical team at Marquis Intelligence attended the webinar, maintaining our commitment to staying up to date with the latest developments in technology, science, and building standards. The event presented cutting-edge guidance in building practices — integrating, for the first time in history, energy efficiency and Indoor Environmental Quality (IEQ).

Panel speakers – leading experts from across the field

The panel featured globally recognized experts:
Pawel Wargocki (DTU), Andrei Vladimir Lițiu (EPB/REHVA), Andreas Martinsson Björkdahl (Svensk Ventilation), and Åsa Norén Lundh, moderated by Mikael Börjesson.

Their shared message was clear: an energy-efficient building cannot be considered high-quality unless it also provides a healthy indoor environment – and healthy air plays a decisive role.

This topic aligned perfectly with insights from the recent D-A-CH conference on comfort ventilation, which also emphasised the importance of healthy indoor air as a core element of indoor environmental quality.

SEE ALSO: Comfort Ventilation: The Mandatory Standard for Indoor Air Quality

1. EPBD 2025: A new philosophy for European building design

For decades, European building policy focused almost exclusively on energy efficiency. The new EPBD brings a crucial shift: a building is not energy-efficient if it fails to provide a healthy indoor environment for its occupants. This includes healthy air, which makes up about 90% of the climate people experience indoors.

Consequently, the EPBD now formally equates energy efficiency with Indoor Environmental Quality (IEQ).

Building performance assessments now must include:

• ventilation and airflow rates
• temperature and humidity control
• CO₂ concentration
• indoor pollutants
• noise, lighting, and other comfort parameters

This marks a fundamental change in how Europe views buildings.

2. Why has IEQ become a pillar of European policy?

The explanation is simple. People spend about 90% of their time indoors, breathing between 12,000 and 15,000 litres of air per day.

Therefore, healthy indoor air — as part of high-quality IEQ — is crucial. It directly influences:

• allergies, asthma, and respiratory conditions
• cardiovascular health
• mental well-being and mood
• sleep quality
• productivity and cognitive functions
• learning ability and concentration
• long-term health outcomes

SEE ALSO: Air Pollution and Diabetes – New Scientific Findings
SEE ALSO: Air Pollution and Cancer – New Scientific Findings

As Wargocki emphasised:
“There is no energy-efficient building if the building is not healthy to occupy.”

The EPBD now incorporates that fact directly into legislation.

3, Europe’s greatest challenge: the existing building stock

Europe has approximately 200 million buildings.
About 85% were built before 2000.
And 75% of the buildings that will be in use in 2050 already exist today.

Therefore, the key to Europe’s transition lies in renovating existing buildings.

The EPBD requires member states to:

• Introduce clear, measurable IEQ standards.
• Deploy monitoring systems (sensors) in a large number of buildings.
• Integrate IEQ into EPC certificates.
• Prevent adverse side effects of energy savings on indoor conditions.
• Link modern renovation practices with health and energy performance.

This represents the most significant transformation in European building policy to date.

4. What does the EPBD now require?

The panel outlined five main pillars of the recast EPBD:

1. Integration of IEQ in energy design – Energy savings must never compromise healthy indoor air.
2. Mandatory monitoring – CO₂, humidity, temperature, airflow and other parameters must be measured and supervised.
3. Minimum IEQ requirements – Member states must enforce standards that prevent health risks.
4. Expanded EPC certificates – EPC ratings now include the building’s health-related performance.
5. Legal obligations for new and renovated buildings – Monitoring and ventilation standards will become mandatory for many building types beginning in 2026.

5. Without monitoring, there is no progress

As Wargocki and Lițiu stressed:  “We cannot improve what we do not measure.”

Monitoring enables:

• real-time control
• failure prevention
• compliance with standards
• automated ventilation management
• optimized energy use
• transparency within EPC documentation
• precise data for building operations

6. Sweden: challenges even in the most advanced countries

Although Sweden is considered a ventilation leader, the presented data were surprising:

• 78% of homes do not meet the minimum requirement of 0.5 air changes per hour.
• Designed airflow rates often differ from real-world values.
• Ventilation system maintenance is insufficient.
• Periodic inspections alone are not enough.

These findings show that the challenges are not local – they are European and global.

7. Between obligations and opportunities

According to industry analysis, the pandemic accelerated awareness of the importance of IEQ. Furthermore:

• Digitalization has enabled reliable measurement and monitoring
• Users want solutions, but often do not understand the underlying complexity
• The industry must provide integrated, easy-to-use systems
• Maintenance is just as crucial as design

The profession’s key message remains:

“Energy efficiency without a healthy indoor environment is not sustainable. And a healthy indoor environment is impossible without energy efficiency.”

Buildings as human ecosystems

The new EPBD changes the way we think about buildings.
They are no longer mere energy consumers – they are becoming human ecosystems.

Europe is therefore shifting its focus to how healthy a building is for the people inside it, and how efficiently it uses energy to secure that quality.

The EPBD is becoming a framework for a healthier, more productive, and more sustainable future for living and working across Europe.

Marquis Intelligence has long emphasized that healthy indoor air is a fundamental prerequisite for a healthy life. According to our experts, people spend about 65% of their lives at home. Ensuring healthy air in that environment is therefore invaluable for human health, well-being, and longevity.

For many years, Marquis Intelligence has been implementing advanced, energy-efficient ventilation and air-purification solutions for homes and buildings of all types.

SEE ALSO: Mini Case Study: Apartment Ventilation in Belgrade

This text by Marquis Intelligence is part of the series “Air Quality and Ventilation Standards.”
Document number: MI-NewLegislation-006.25 – EPBD: Energy-Efficient Buildings Need Healthy Indoor Air.