Located in a brutalist former bank headquarters in Stockholm, Universal Design Studio's latest project, the At Six hotel, is home to one of Europe's most significant hotel art collections.

The London-based studio carried out a complete interior renovation to create the 343-room luxury hotel in the Swedish capital's Brunkebergstorg Square, and also designed a new entrance.

The scheme includes 10 floors of guest rooms, a penthouse suite, a 100-cover restaurant, a wine bar, cocktail bar, a 2,000-square-metre events and flexible work space, and Scandinavia's first slow listening lounge.

The art collection is curated by Sune Nordgren, formerly of the BALTIC Centre for Contemporary Art. Works by Jaume Plensa, Olafur Eliasson, Julian Opie, Sol Le Witt, Tacita Dean, Spencer Finch, Richard Long and Marijke van Warmerdam are displayed within the public spaces, while individual artworks by Kristina Matousch are showcased in the guest rooms. Works by Swedish photographer Dawid complete the hotel art collection.

The monochrome interior contrasts shades of warm grey and highly textured natural materials with soft furnishings and classic furniture editions. The aim was to reinterpret the brutalist aesthetic of the building and the immediate architectural landscape of Brunkebergstorg Square.

"A palette of sawn stone, blackened steel, fine timber and polished granite lends a sense of permanence and authenticity to the new interior," explained Universal Design Studio, which was set up by design duo Edward Barber and Jay Osgerby in 2001 to focus on architecture and interior projects.

"Moving away from the uncompromising and unforgiving aesthetic characteristics often associated with the brutalism – [our] brief was to create a desirable, fashionable destination," said the team.

"[Our] design is focused on humanising the architecture, bringing a sense of desirability and luxury to a brutalist building not often associated with these traits, turning the hotel into a contemporary version of a metropolitan grand hotel."

Pieces of contemporary and classic furniture are complemented by specially commissioned pieces created by local makers and established Scandinavian designers.

Custom lighting by Rubn is installed in each guest room, and local glassmaker Carina Seth Anderson has created a series of sculptural, hand-blown glass vessels for the lobby as well as tabletop pieces for each dining table in the restaurant.

The handrail of the grand white granite staircase in the hotel's lobby was wrapped in leather by a local saddle maker, while a communal table in the wine bar was carved by local artist Lies-Marie Hoffman from a single Swedish elm trunk.

Bedrooms feature timber wall panelling and marble credenzas that run the full length of the room.

The hotel is one of four 1970s buildings that occupy Stockholm's Brunkebergstorg Square. The buildings were built during a government initiative that aimed to replace much of the city centre's belle époque grandeur with brutal modernity.

Although the high-rise building was originally designed by Swedish architects Boijsen & Efervgren as a hotel, it ended up functioning as the headquarters of Swedbank, never fulfilling its intended purpose.

Now owned and operated by Petter Stordalen of Nordic Hotels & Resorts, the hotel is at the centre of a wider regeneration programme that aims to transform Brunkebergstorg Square into a social hub within the city.

Universal Design Studio ranked at number 128 on the inaugural Dezeen Hot List. The studio has previously designed the Ace Hotel in Shoreditch, a store in Mayfair for fashion brand J&M Davidson, and a pink terrazzo interior for a restaurant interior in Singapore.

Photography is by Andy Liffner.