In 2013, 20 Fenchurch Street, famously nicknamed the “Walkie Talkie” due to its distinctive, bulbous shape, opened in London’s financial district. The building’s innovative curved glass façade quickly captured attention, not just for its architectural boldness, but for an unforeseen problem. The concave glass acted like a giant magnifying glass, concentrating sunlight intensely onto the streets below, creating a powerful urban heat ray.
The Heat That Melted Metals and Burned Surfaces
This solar concentration caused temperatures to soar as high as 91°C (196°F), enough to melt and warp various materials. One of the most publicized incidents involved a Jaguar XJ parked nearby, whose wing mirror and car panels were damaged by the reflected heat. Surrounding businesses also reported cracked tiles, blistered paintwork, and even holes burned through doormats and carpets. The sheer intensity of the reflected sunlight posed not only property damage but a safety risk to pedestrians in the area.
Swift Action: Temporary Measures and Permanent Solutions
In response to the problem, the building’s developers, Land Securities and Canary Wharf Group, quickly installed temporary black mesh screens to shield the affected areas from the concentrated rays. However, a more sustainable solution was necessary. Following planning approval, a permanent “brise soleil”, a sunshade structure, was installed to deflect and diffuse sunlight, effectively neutralizing the damaging glare.
From Controversy to Landmark
Despite its fiery debut, 20 Fenchurch Street has since become an iconic part of London’s skyline. Its Sky Garden atop the building offers sweeping panoramic views of the city, drawing visitors and locals alike. The story of the Walkie Talkie’s solar glare serves as a compelling lesson in architectural innovation and the importance of considering environmental impacts in urban design. 
Source: London Evening Standard with additional information added by Glass Balkan
