Alor, Luxembourg

Alor Building – Luxembourg
Project overview

The Alor building in Luxembourg underwent a façade retrofit to improve thermal and visual performance. Designed by Ballini, Pitt + Partners, the project uses a rear‑ventilated double‑skin façade with motorised retro‑reflection using Fresnel optics
retrosolar.us
. The building hosts offices and aims to provide modern amenities while reducing energy consumption.

Design challenge

The existing façade lacked effective shading and suffered from glare and overheating. The retrofit had to deliver improved performance while working within the constraints of the existing structure. The shading system needed to be automated to ensure continuous operation without user input. Managing visible reflections was also important to avoid disturbing neighbouring buildings and pedestrians.

RetroSolar strategy

The designers selected RETROFlex blinds installed in the cavity of the double‑skin façade
retrosolar.us
. These blinds are motorised and equipped with Fresnel optics that precisely direct light, preventing unwanted reflections and glare. The rear‑ventilated cavity allows heat to escape, and the Fresnel optics ensure that light is either reflected back out or redirected upwards, avoiding glare in adjacent buildings. This arrangement delivers effective shading and daylighting while preserving the building’s glass façade.

Building physics and performance

The motorised RetroFlex blinds reduce solar heat gain and glare, improving occupant comfort. The rear ventilation of the cavity dissipates heat, preventing the façade from overheating. Fresnel optics minimise visible reflections, ensuring that the building does not create glare for its surroundings. The automated system operates based on solar conditions, ensuring consistent performance without user intervention.

Architectural outcome and significance

The Alor retrofit provides a sophisticated solution that combines high performance with a refined aesthetic. The motorised blinds are hidden within the cavity, and the Fresnel optics allow the glass façade to appear clear and unobstructed. This project underscores the potential of RetroSolar technology in retrofitting existing buildings to meet contemporary energy and comfort standards while maintaining architectural quality.