Bezons, France


Key Facts

First building in Continental Europe

  • to achieve a WELL Building Standard Certification

130,000 square-foot

  • office building

Climate Based Daylight Modelling performed

  • for credit 62 – Daylight Modelling

ASHRAE 55 analysis performed

  • for credit 76 - Thermal Comfort

The SCENEO project, a 130,000 square-foot office building in Bezons, France, is the first building in Continental Europe to achieve a WELL Building Standard Certification at Gold level. IES Consulting provided daylight (cr 62) and thermal comfort analysis (cr 76) services toward the WELL Building Standard.

Credit 62 – Daylight Modelling

IES Consulting used RadianceIES climate based daylight modelling (CBDM) technology to model the space performance. CBDM utilises an annual simulation linking location, shading, climate data (including solar intensity and cloud cover) together with the building properties. This provides a complete overview on how the daylight performance varies throughout the year due to changes in these factors.

The analysis included performance against sDA (spatial daylight autonomy) and ASE (annual sunlight exposure).

CBDM is more detailed than a static calculation which provides only a snap shot approach. Daylighting varies throughout the year, primarily due to the solar position, so it is essential daylighting variance is properly considered toward the impact on building design.

To achieve WELL credit 62, it requires that:

  • Spatial daylight autonomy (sDA 300, 50%) is achieved for at least 55% of regularly occupied space. In other words, at least 55% of the space receives at least 300 lux [28 fc] of sunlight for at least 50% of operating hours each year.
  • Annual sunlight exposure (ASE 1000, 250) is achieved for no more than 10% of regularly occupied space. In other words, no more than 10% of the area can receive more than 1,000 lux for 250 hours each year.

The analysis performed by IES consulting showed that the sDA criteria would not be met with the design conditions at that time, however the ASE criteria was met sufficiently to comply with that part of the credit. These results equipped our client with knowledge of the changes required to fully comply with WELL credit 62.