The extensive modular façade not only screens the sun from the building strategically, but it also provides interest and beauty. Between the vertical exterior screen and the glass facade of the building is a perforated metal footbridge for maintenance. The footbridge also serves as a horizontal bris-soleil to shade the building on the south side. And thus this smart combination of horizontal and vertical shading protects the building from solar thermal heat gain, thereby reducing its need for air-conditioning.
Though the building is designed to mitigate solar thermal heat gain, the architects didn’t block out the sun completely. To reduce reliance on energy-consuming lighting, Ravetllat-Ribas designed each space so that it would be illuminated by natural light. Naturally day-lit interior spaces not only help reduce energy bills, but they also provide a more enjoyable experience for the building’s inhabitants.
Radio Nacional Headquarters is an excellent example of how smart passive solar design can go a long way in reducing a building’s carbon emissions, while also achieving architectural interest and a pleasant user experience.