Nursery & primary school in Biol (38)
How to deal with the sun’s rays?
As part of the construction of a kindergarten and elementary school in Biol, we carried out a shading study for the east and west facades to propose an optimal solution for managing solar radiation. The main objective was to reduce solar gain as much as possible in summer, while maintaining a good level of natural lighting and warmth in winter.
The study
We analyzed the solar reception of unprotected facades to understand the direct impact of radiation. The results show that both the east and west facades are exposed to direct sunlight. Given the large bay windows on these façades, the installation of sunshades seems essential to limit excessive heat gain.
Solar reception without sunshade
An analysis of the solar radiation received by facades without sunshades has enabled us to draw up an inventory of the situation. The maps below illustrate direct solar radiation reception by month and time of day for each façade:
East facade
West facade
On the east facade, exposure to direct sunlight begins at sunrise and continues until mid-day. The west façade then takes over, capturing the sun’s rays until the end of the day.
Given the large surface area and number of windows, the addition of solar shading devices is necessary to limit excessive solar gain.
Solar reception with sunshade
After studying the configuration with TELLIER AZUR AS300x5 type sunshades, installed vertically with the blades laid down.
The effectiveness of the sunshades was simulated according to the inclination of the blades and their positioning, adapted to the façade.
Sunshade technical details:
- Blade width: 0.300 m
- Blade thickness: 0.052 m
- Blade pitch: 0.305 m
Sunshade control scenario
To optimize the efficiency of the brise-soleil, an automatic control scenario has been defined based on the sun’s elevation and position (azimuth). Control varies according to season:
Winter period (October 1 – April 30): Blades are tilted at 0° to maximize solar gain.
Summer period (May 1 – September 30): Blades are controlled according to the position of the sun, to ensure optimum shading between the defined azimuth angles. Outside these periods, the blades remain horizontal (0°) to maximize natural light.
Azimuths and control periods :
East facade: 45° to 135° (morning)
West facade: 225° to 315° (afternoon)
Analysis of results
East facade :
The table on the right shows the ratio of radiation and illuminance received compared to a configuration without brise-soleil, for different fixed slat inclinations over the whole year. This makes it possible to assess the effectiveness of each tilt.
East facade: Radiation & illuminance ratio
East facade: With optimized blade control
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Global radiation | 0.60 | 0.59 | 0.58 | 0.55 | 0.37 | 0.37 | 0.35 | 0.37 | 0.37 | 0.58 | 0.60 | 0.60 |
| Direct radiation | 0.52 | 0.50 | 0.46 | 0.39 | 0.03 | 0.06 | 0.05 | 0.06 | 0.04 | 0.47 | 0.52 | 0.53 |
| Overall illuminance | 0.58 | 0.57 | 0.56 | 0.54 | 0.42 | 0.43 | 0.41 | 0.42 | 0.42 | 0.56 | 0.58 | 0.58 |
| Direct illumination | 0.50 | 0.46 | 0.43 | 0.6 | 0.02 | 0.03 | 0.04 | 0.04 | 0.03 | 0.42 | 0.49 | 0.50 |
West facade :
The table on the right also shows the ratio of radiation and illuminance received compared to a configuration without brise-soleil, for different inclinations of fixed louvers over the year, enabling the performance of each inclination to be compared.
West facade: Radiation & illuminance ratio
West façade: With optimized blade control
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Global radiation | 0.59 | 0.57 | 0.54 | 0.54 | 0.41 | 0.42 | 0.38 | 0.40 | 0.41 | 0.55 | 0.57 | 0.56 |
| Direct radiation | 0.46 | 0.43 | 0.33 | 0.34 | 0.04 | 0.04 | 0.03 | 0.02 | 0.02 | 0.38 | 0.41 | 0.35 |
| Overall illuminance | 0.57 | 0.56 | 0.54 | 0.54 | 0.46 | 0.47 | 0.44 | 0.46 | 0.46 | 0.54 | 0.55 | 0.56 |
| Direct illumination | 0.41 | 0.38 | 0.29 | 0.31 | 0.04 | 0.04 | 0.03 | 0.02 | 0.02 | 0.34 | 0.35 | 0.33 |
Results
This study demonstrates the effectiveness of external venetian blinds in optimizing thermal and lighting comfort in the Biol school. Thanks to seasonally-adapted control, the louvers considerably reduce solar gain in summer, while preserving light and heat in winter. This solution balances energy performance with visual comfort for occupants.
