Submetering: consumption measured where it is used.
Submetering records how much heat, water or energy each unit in a building uses. It turns one building-level figure into individual consumption data for every flat, office or commercial unit. That data is the basis for consumption-based billing, for transparency for the people who use the building, and for decisions about its energy performance.
Individual consumption data
Billing based on actual use
Transparency during the year
Support for metering duties
What submetering means
Every building has a main meter. It records what the whole building draws from the grid or from the district heating network: heat, water, gas or electricity. The main meter answers one question only, namely how much the building consumed in total. It cannot show which unit that consumption came from.
Submetering closes that gap. Sub-meters and heat cost allocators are installed inside the building, at the point where energy or water is actually used: at radiators, at heating circuits, on water pipes, in the electrical distribution board. The devices are read regularly, and the readings are used to allocate the building's costs to its individual units.
The term itself is descriptive. "Sub" refers to the level below the main meter. Submetering is therefore not a single device or a single service, but the combination of metering technology, data transmission, data processing and billing.
Why individual measurement matters
Without individual data, the costs of a multi-occupancy building have to be split by a fixed key, usually floor area. Two units of the same size then pay the same amount, even if one heats every room to 24 degrees and the other keeps two rooms unheated. Individual measurement replaces that assumption with a measured value.
This has three practical effects:
- Cost allocation becomes verifiable. Every user can trace their share of the total cost back to their own consumption.
- Consumption becomes visible. People can only change what they can see. Regular consumption information gives users a reference point during the heating period, not only at the end of it.
- Buildings become comparable. Consumption data per unit, per building and per portfolio shows where a portfolio's energy use is concentrated and where refurbishment or heating optimisation is likely to pay off.
For property owners and managers, individual measurement is also a legal matter. In the European Union, consumption-based metering and billing in multi-occupancy buildings is required by law, and comparable rules exist in many countries outside the EU.
Metering and billing rules in Europe
The European Energy Efficiency Directive sets the framework for individual metering and consumption-based billing in buildings with several users, where this is technically feasible and cost-effective. Two requirements shape how buildings are equipped today:
- Newly installed meters and heat cost allocators must be remotely readable.
- Devices that are already installed and not remotely readable must be made remotely readable or replaced by 1 January 2027.
In addition, users must receive consumption information on a monthly basis where remotely readable devices are in place.
Each country transposes the directive into its own national law. Deadlines, exemptions information and the rules for cost allocation therefore differ. The details for a specific market are described on the respective ista country website.
Submetering for every project
Housing companies and property manager
Large portfolios need reliable data for many buildings at the same time. Remote reading removes appointments in occupied flats, and standardised data delivery makes annual billing plannable.
Landlords and owners
Owners of one or a few properties need a correct billing and clear evidence of what was measured. Submetering provides both, without the owner having to read devices or interpret technical data.
Commercial and industrial property
Commercial and industrial buildings often have complex energy systems, multiple tenants and different usage patterns. Submetering provides accurate consumption data for individual units and areas, enabling transparent cost allocation, reliable billing and better monitoring of energy consumption.
Heating
Water
Cooling
How consumption data becomes a billing
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Metering concept: Supply structure, existing devices, number and type of units — we look at these first. The result defines what is measured where, and with which technology.
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Installation: Devices are fitted to radiators, pipes and distribution boards. Existing meters can often be integrated instead of replaced.
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Automated reading: Devices send their readings by radio to a collection point in the building, which forwards them to our systems. Nobody has to enter a unit.
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Data check: Readings are checked for plausibility and completeness. Missing or implausible values are followed up and, where needed, substituted under the applicable rules.
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Consumption information and bill: Users see their consumption during the year. At the end of the billing period, the measured values produce the bill, following local cost allocation rules.
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Operation over the device lifetime: Meters are verified or replaced at defined intervals, and radio networks are monitored. Both are part of the service, for as long as the building needs it.
Consumption data and data protection
Consumption data can be linked to individuals, so it is treated as personal data. That shapes how we work with it: access is restricted, data is used for the purpose it was collected for, and processing follows the applicable data protection law, in the European Union the General Data Protection Regulation. Which data a landlord, a manager or a resident may see is defined by their respective role.
What submetering data is also used for
Once consumption is measured per unit, the same data supports further services. On this website you will find general information about each of them; the services available in a specific market are listed on the country website.
- Billing services Preparation of heating, water and service charge billing on the basis of the measured values.
- Energy monitoring Consumption data for buildings and portfolios, visualised over time, as a basis for energy management.
- Heating optimisation Continuous analysis of heating system data, with automatic adjustment of the system's settings.
- Reporting on energy and emissions Consumption data as an input for building-related energy and emissions reporting.
Frequently asked questions
The main meter records the consumption of the whole building and is the basis for the supplier's invoice. Submetering records consumption inside the building, per unit, and is the basis for splitting that invoice between users.
Yes. Heat cost allocators, water meters and heat meters are designed to be retrofitted, and radio transmission avoids new cabling in most cases. What is technically sensible depends on the building, which is why a metering concept comes before any installation.
Remotely readable devices record and transmit values regularly, which makes consumption information during the year possible. The billing itself is prepared for the billing period defined in the contract or in national law, usually twelve months.
Metering duties, billing deadlines and cost allocation rules are set by national law. The ista country website for your market describes what applies there.
ista worldwide - Submetering in your country
Submetering is part of our services in every market we operate in. The available devices, service models and reporting formats differ, because building stock, supply structures and national law differ. The country websites describe what we offer locally, in the local language, and who to speak to.