Among the European standardisation committees dedicated to the Energy Performance of Buildings, CEN/Technical Committee 156 deals with all aspects of ventilation.

This committee launched through its 12th Working Group a new standard (prEN 15251) concerned with criteria for a satisfactory indoor environment (including thermal, indoor air quality, light and noise) . The need for the standard arises from the 2002 Directive on the Energy Performance of Buildings.

ECOS has concerned that this process would not clearly protect the indoor environment and will therefore lead to a possible reduction in satisfaction among building occupants. There could also be a threat that by trying to improve their comfort, building occupants would undermine energy savings by privileging energy-consuming air-conditioning over natural “passive” cooling. Thus, there are concerns that comfort categories may encourage the use of unnecessarily highly energy-consuming devices.

ECOS has sent an expert to this committee since 2005 and has already provided comments on:

  • calculating the mean outdoor temperature with a method that better takes into account variations in weather,
  • the definition of thermal limits for summertime in naturally ventilated buildings using the theory of adaptative thermal comfort,
  • the issue of the validity of establishing building categories according to the way of controlling indoor climate,
  • a broader range of humidity in buildings, to discourage the use of extensive and energy-consuming humidification or dehumidification.