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What flow rates does your home need?
NBN D50-001 derives a room's flow rate from its floor area: 3.6 m³/h per m², constrained between a minimum and a maximum specific to the room type. Enter your rooms below.
Supply
108m³/h
Supply
50m³/h
Supply
40m³/h
Extract
50m³/h
value raised to the standard's minimum · 43 m³/h
Extract
50m³/h
value raised to the standard's minimum · 22 m³/h
Extract
25m³/h
- Total supply air
- 198m³/h
- Total extract
- 125m³/h
Supply and extract differ noticeably. In a heat-recovery system the two totals must balance: the higher total determines the airflow to install.
Indicative result, provided for information. For a project under EPB regulations, the reference calculation is the one produced by the EPB reporter appointed to your project.
And in reality, does your system reach those values?
The calculation says what should be. Only a flow meter says what is. That is exactly what we do during an assessment.
What your region requires
Flow rates are calculated to NBN D50-001 everywhere. What changes between regions is how compliance is verified on a project.
| Region | What applies | Who is responsible |
|---|---|---|
| Brussels-Capital Region | Ventilation provisions required in new build and certain renovations fall under Brussels EPB regulations. Flow rates are calculated to NBN D50-001. | The EPB adviser appointed to the project |
| Walloon Region | Hygienic ventilation is part of Walloon EPB requirements, with minimum flow rates set by room area and use, in line with NBN D50-001. | The project's accredited EPB officer |
| Flemish Region | Flanders goes further than the other two regions: since 2016, every EPB-regulated project requires an accredited ventilation reporter, separate from the EPB reporter. They produce a pre-design before works, then measure actual flow rates after installation. | An accredited ventilation reporter, alongside the EPB reporter |