Custom software for the BACS requirement
The obligation for a building automation and control system applied from 31 December 2025 at the latest. That date has passed, and a large share of non-residential buildings do not comply. The reason is rarely unwillingness: it is often unclear which buildings are affected, and installing a system is not the same as demonstrating that it does what the requirement asks.
What the requirement precisely asks
The obligation is set out in the Besluit bouwwerken leefomgeving, with separate articles for existing buildings and new construction. It applies to buildings without a residential function that have a heating or cooling installation with a nominal capacity above 290 kilowatts. The threshold applies separately to heating and to cooling, and concerns installations that are hydraulically or refrigeration-wise connected to one another.
The system must be able to do three things. Continuously monitor, record and analyse energy consumption. Assess efficiency, detect losses and inform the manager accordingly. And communicate with the technical building systems and be interoperable with equipment from different manufacturers. The third point is where many existing building management systems fall short.
The word analyse does most of the work in that list. A system that displays readings is not enough: it must detect losses and inform the manager. That is an active obligation, and it is also what enforcement by the regional environmental service ultimately turns on. Moreover, this is not the end point: under the revised European directive, the threshold for utility buildings drops to above 70 kilowatts by the end of 2029 at the latest. If you build something now, you are building for a larger portfolio.
Alongside this obligation, there is an inspection requirement for the installations themselves, with a much lower threshold: air conditioning from twelve kilowatts. See software for the EPBD inspection requirement.
How we build this
The installation itself remains your installer's responsibility. We build the layer on top: collecting, analysing and demonstrating that it is happening.
Calculating the capacity threshold per building is the real work in a portfolio. Without that list, you don't know where to start, nor when you are finished.
Boilers, chillers, air handling and meters rarely speak the same language. We retrieve what exists and normalise it into a single format, so that buildings become comparable.
Heating and cooling at the same time, night setback that is switched off, a valve that won't close. These are patterns, and you find them with rules applied to time series, not with a chart.
The requirement explicitly mentions informing. A notification with a cause and a responsible party is something different from a dashboard that someone could have opened.
What the software actually does
The collection and analysis layer carries the whole. What else you need depends on the size of your portfolio and on what installation is already in place.
Determining which buildings fall under the requirement
For each building, the installed capacity for heating and cooling, with the justification attached. That is the first question from the environmental service and usually also the question still open internally.
Continuously tracking consumption
Measurement values from installations and meters arrive continuously and are stored at a fixed time interval. Without history, analysis is impossible, and demonstrating compliance is too.
Detecting losses with rules on the series
Simultaneous heating and cooling, missing night setback, a setting that did not return after a fault. Patterns that become visible over days, not in a snapshot.
Comparing buildings side by side
Consumption per square metre and per degree day makes buildings comparable. The outlier in your own portfolio is the cheapest place to start.
Connecting to what is already there
Existing control systems and meters speak a range of different protocols. We bring them together through integrations rather than requiring new installations.
Demonstrable to the competent authority
What was measured, which deviations were reported and what was done about them, in a form you can present. Complying and being able to demonstrate compliance are two different things.
Who we build for
The requirement affects very different buildings. Four situations in which this arises.
Owners with multiple properties
This is where the benefit of comparison lies. One building that structurally uses more than a comparable property is the first place to look. See also energy management software.
Healthcare and education
Large installations, tight budgets and buildings that cannot be shut down. The analysis must therefore point to settings that cost nothing, not to replacement. See also facility management software.
Mixed ownership with a residential function
The requirement applies to the part without a residential function. In mixed complexes, delineation is the tricky point, and you want that documented with justification.
Installers and maintenance companies
You manage installations for several clients. An environment in which you can show each client what is happening turns your maintenance contract into a demonstrable service. The on-site round runs through the installation inspection app.
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The threshold is changing, and the designated standard may be revised. Anything related to limit values, analysis rules and reporting formats should be configurable.
Why Appfront
The first question is which buildings are concerned
We start with the power determination and its justification. Without that list, you would be building something without knowing whether it is sufficient.
Analysis is the requirement, not measurement
We build rules that detect losses. A dashboard that merely displays values does not meet what is being asked.
Connecting to what is already there
Replacing your installation is rarely necessary and always expensive. We retrieve what the existing equipment already produces.
Demonstrability is the goal
The regional environmental service does not ask whether you have a system, but what it has done. We build that in as a fixed part rather than as a separate report.
Security and privacy
Energy consumption data per building says more than it appears to. A consumption profile can reveal when a property is empty, and that is information you do not want to share widely. We set access per building and per role, give a management party access only to its own buildings, and log every inspection.
On the measurement side, a requirement weighs heavily here. You must later be able to show what was measured and what was done about a deviation, and that only works if the series has not been retrospectively altered. We keep measured values unalterable with their original timestamp and make any correction visible alongside the old value. How we handle security ourselves is set out in our information security policy; reports from outside go through our CVD policy.
Frequently asked questions about the BACS obligation
The requirement applies to non-residential buildings with a heating or cooling installation above a nominal output of 290 kilowatts. The threshold applies separately to heating and to cooling. The precise determination is set out in the Building Works in the Living Environment Decree (Besluit bouwwerken leefomgeving); have the calculation for your situation checked by an installation adviser.
The final deadline was 31 December 2025, and it was widely missed, partly due to uncertainty about the requirements and tightness in the market. That does not make the obligation any less valid. Regional environmental services are supervising, and it helps to be demonstrably working on it rather than having done nothing.
Not automatically. Many existing systems control but do not analyse, and do not actively inform the manager of losses. Interoperability with equipment from different manufacturers is also an explicit requirement, where older installations often fall short. What is usually missing is the layer above, not the installation itself.
Usually not. The requirement concerns automation and control, not generation. In practice it is more often a matter of unlocking and analysing data than replacing boilers. That distinction is the difference between a project and an investment.
The Bbl designates NEN-EN-ISO 52120. It is in English and there is no Dutch translation. For practical explanation, an interpretation document from industry bodies is in circulation. We apply the requirements as a matter of principle, so that a revision does not become a rebuild.
Yes. Under the revised European Energy Performance of Buildings Directive, the threshold for non-residential buildings drops to above 70 kilowatts by the end of 2029 at the latest. That significantly increases the number of buildings in scope. If you are setting this up now, it is worth mapping out your wider portfolio straight away.
The environmental service acting on behalf of the competent authority. In practice this comes up during an inspection visit or another request relating to the building. The questions are then what the system does and what has happened to any deviations found, and that is a records question.
That depends on the number of buildings, how much metering data is already available and how varied the installations are. Determining capacity and pulling in existing metering data are usually quick; the analysis rules then grow in step. We provide a substantiated estimate after the scoping phase.
Do you know which buildings fall under the requirement?
Take one building you think is in scope and try to establish, with supporting evidence, the installed capacity for heating and cooling. That is where it starts. We build this as a standalone application and as part of a broader custom software project.