Case Study on EN 16798-7 : Natural Ventilation

This case study dutifully demonstrates the calculation of natural ventilation by coupling of the spreadsheets to the standards EN ISO 52016-1 and EN 16798-7. As a valid example, we have used the single family house model from CEN_ISO/TR 52016-2. An opening pattern of the east and west windows is used for natural ventilation purposes, using the simplified calculation for openable windows of EN 16798-7. Four cases are calculated, with tow variants each:

  • A winter period for an average climate showing the difference between continuous and intermittent airing 3 times a day and its influence on the heating needs: 

The heating needs show peaks at every hour when the intermittent airing is active, often reaching the maximum power, while the continuous airing variant shows a more evenly distributed heating power with peaks in the morning at the starting point of the heating operation.  

  • A summer period for an average climate showing the influence with and without ventilative cooling on the zone operative temperature: 

The ventilative cooling operation leads to considerable lower indoor operative temperatures (maxima always below 27°C) than without ventilative cooling (maxima above 30°C). 

  • A summer period for a warm climate, also showing the influence with and without ventilative cooling on the zone operative temperature: 

While the indoor temperature without ventilative cooling is far too high, it is lower with ventilative cooling, but still not in a comfortable range. This shows the limitation of the ventilative cooling in this climate, mainly due to the high night time temperatures. 

  • A whole year hourly calculation for a warm climate showing the influence with and without ventilative cooling on the cooling energy needs:

 

The annual cooling needs can be reduced by ventilative cooling by 50%, with the reduction varying between 100% (intermediate season) to 14% during the hot summer months. 

 

The case study demonstrates and proofs the functionality of the simplified openable window calculation in interaction with the energy needs for heating and cooling and the temperature calculation for a thermal zone.

 

More details on the calculation methodology and the impact it has on various building types, either residential or corporate, can be found in the full document, which can be accessed at the link below:

 

Report Case Study on EN 16798-7 : Natural Ventilation