A healthy building you cannot see. You must measure it.

Dutch people spend most of their time indoors. Yet most building owners don't know what the indoor climate looks like on any given Tuesday afternoon. The figures show how large the challenge is:

• In about 80% of classrooms and roughly 60% of homes, the CO2 limit of 1,200 ppm is periodically exceeded.
• Almost three out of ten social housing tenants experience mold issues. In Amsterdam, it's roughly 40% of social rental homes.
• During heat waves, elderly residents and clients in care facilities, who adapt less well to heat, face direct health risks.

It's not about the exact number. It's that unhealthy indoor climate is more rule than exception, and without measurement it remains invisible.

First: indoor climate is not a fixed building property. It changes hour by hour, room by room, and with every occupant. A classroom that's fresh at 8:30 AM can be well above normal by 11:00 AM. A home with four occupants behaves differently than the same home with two.

Second: a single snapshot doesn't tell the whole story. One measurement or a resident's complaint shows something is wrong, but not why, when, or how often. Only continuous data reveals patterns.

Third: measuring is cheaper than blind replacement. Know the cause, invest deliberately. Sometimes a new ventilation system is needed. More often, it's a matter of settings, usage, or maintenance.

The same data platform we use for energy management and grid congestion, focused on the health of your building. Three steps in one continuous cycle.

Individually, a measured value tells little. Together, they show exactly what's happening in a room:

CO2 (ppm). The best indicator of ventilation relative to occupancy. If CO2 rises quickly, the air isn't being refreshed enough for the number of people present.

Relative humidity (%). If this remains high for long, the risk of condensation and mold increases significantly.

Temperature (°C). Determines thermal comfort and, together with humidity, the dew point: the temperature at which moisture condenses on cold surfaces.

Air pressure (hPa). Helps better interpret pressure differences and ventilation performance.

Example: mold unraveled. High humidity together with high CO2 suggests insufficient ventilation for occupancy—for instance, many residents in a small space. High humidity with normal CO2 more likely points to a moisture source like a leak or rising damp. A consistently small difference between room temperature and dew point indicates elevated risk of condensation on cold spots. This way you distinguish behavior from building physics, with data instead of assumptions.

Why no ABC correction? Many CO2 sensors automatically correct themselves periodically to an assumed 'clean' outdoor air value (Automatic Baseline Correction). In spaces that are almost always occupied—like homes and care rooms—the air never gets clean, and such a sensor underestimates actual concentration. Our sensors measure without ABC correction, so measurements across months and hundreds of rooms remain reliably comparable.

Housing associations: detect mold before it becomes a complaint
Damp and mold complaints are persistent because the cause differs per home. Continuous measurements show each home whether the issue lies in ventilation, occupancy, or building physics. This way you prioritize maintenance based on facts, support communication with tenants, and see after an intervention whether the measure actually worked. The sensors have no display and no lights: residents notice nothing and don't need to do anything.

Care facilities: comfort and safety for vulnerable residents
Elderly people and clients are more sensitive to heat and poor air quality, and can't always communicate this themselves. With temperature measurements per room, during a heat wave you immediately see which rooms get too warm, so care staff can act decisively. CO2 measurements provide insight into ventilation, a key part of infection control. At the same time, you see where unnecessary heating or cooling occurs.

Schools: a fresh classroom is a better classroom
Since July 1, 2025, a CO2 meter is mandatory in every classroom in primary and secondary education. A meter in the classroom helps the teacher in the moment. A central platform helps the school board: which classrooms consistently score poorly, where does ventilation fall short, and where is investment worthwhile? With data you can measure against the Fresh Schools Program of Requirements, which uses a CO2 limit of 950 ppm for Class B and 800 ppm for Class A.

Offices: healthy air, sharper staff
Research by the Harvard T.H. Chan School of Public Health showed that cognitive test scores of office workers were on average 101% higher with improved ventilation than in a conventional office. Meanwhile, many offices over-ventilate and over-heat spaces that sit empty. Measuring based on actual occupancy improves comfort and cuts energy costs. And under workplace health and safety law, as an employer you're responsible for a healthy work climate.

With the revised European Energy Performance of Buildings Directive (EPBD IV), indoor environmental quality is for the first time explicitly part of European building regulations. Member states had to transpose the directive by May 29, 2026. New zero-emission utility buildings, and buildings undergoing major renovation, must be equipped with monitoring and control systems for indoor air quality. In the Netherlands, from May 30, 2026, there's also a requirement for monitoring and control equipment for indoor environmental quality in new construction and major renovation of residential buildings.

Additionally, the GACS requirement for building automation in utilities shifts from installations above 290 kW to installations above 70 kW (by end of 2029 at the latest). Schools have a CO2 meter requirement, employers have workplace health and safety law, and care facilities have the National Heat Action Plan. Continuous measurements are the proof in all these frameworks that you're actively monitoring indoor climate. (Source: European Commission, IPLO, Dutch Government; terms and implementation in the Building Decree may still change.)

A healthy building is not a cost item but an investment that pays for itself in multiple ways:

• Healthier occupants. Fewer complaints like headaches, fatigue, and respiratory problems, and less absence among staff and students.
• Better performance. Clear air means better concentration in the classroom and office. In practice, we see up to 10% higher productivity.
• Lower energy costs. Ventilating and heating based on actual occupancy instead of standard schedules delivers up to 30% savings in HVAC costs.
• Targeted maintenance. Invest in homes and spaces that really need it, and demonstrate after an intervention that a measure worked.
• Demonstrable compliance. One data trail for EPBD, GACS, Fresh Schools, workplace health and safety, and your own reporting. With automatic reports per location and period.

Accurate without ABC correction. Reliable CO2 data, even in spaces that are rarely empty.

Plug-and-play, no gateway. Sensors connect directly via WiFi and are operational within five minutes. No extra network hardware, no technician, relocated as easily as installed.

Ten years without a second thought. No batteries, powered by USB or mains, and built to last ten years without updates.

Unobtrusive. No display, no lights, no noise. Users and residents notice nothing.

Brand-agnostic. Cobradash works with all brands and types of sensors, including sensors you already have. Thanks to open standards and a uniform interface across brands.

Scales to thousands of sensors. The platform is built and tested to handle large volumes of data from thousands of sensors simultaneously. Already more than 1,200 sensors active in the Netherlands, with 99.9% platform availability.

Dutch and secure. Developed in Badhoevedorp and built in Zaandam. Data on Dutch servers in Amsterdam, not with Microsoft or Amazon. GDPR-compliant, encrypted with TLS and AES-256, and with security certified by HPE (Juniper).

Open and connectable. REST API, webhooks, CSV export, and integrations with your building management system. No vendor lock-in.

De Bouwhuis, home to FME and numerous other industry organizations, is becoming a large-scale testbed for healthy indoor climate within the Indoor Climate Label Fieldlab. Cobra Climate is the technology partner and continuously measures air quality in the conference center. Especially in heavily used conference rooms with fluctuating occupancy, continuous monitoring reveals what periodic checks miss: how quickly air quality declines and whether ventilation keeps pace.

Unhealthy indoor climate is a real problem, but rarely an unsolvable one. Organizations that make a difference don't start with expensive renovation but with an honest look at what's happening in their building. Often the solution is already within reach: a different setting, an adjusted schedule, targeted maintenance where it's needed. With the Climate Bundle (Climate Sensoring and Climate Director, including six months of software), you'll know in short order how your building really is. A straightforward first step with immediately useful insight.

Learn more about the products and insights behind a healthy building.

01. The software: Climate Director
The platform that turns your climate data into insight and action. From portfolio overview to individual room, with alerts, AI analysis, and automated reports. Climate Director →

02. The hardware: Climate Sensoring
Accurate, continuous measurements of CO2, temperature, humidity, and air pressure. Plug-and-play, no gateway, and built to last ten years. Climate Sensoring →

03. Article: De Bouwhuis as a testbed
How Cobra Climate, as technology partner, contributes to the Indoor Climate Label Fieldlab in De Bouwhuis in Zoetermeer. Read the article →

04. Article: Why Cobra Climate offers the smartest CO2 monitoring
From sensors without ABC correction to a scalable platform: what sets our solution apart. Read the article →