Vauxhall may not be the most obvious place for an ambitious art complex, yet this is indeed where the new gallery for Damien Hirst's collection can be found, quietly nestled behind the train track and arches in South London, occupying almost half of the small street. 

Designed by London-based Caruso St John - of New Art Gallery Walsall and Tate Britain Milbank Project fame - Newport Street Gallery is an intriguing collage of five buildings. Each holds its distinct façade, yet the composition forms a coherent whole - the architects treated it as a unified complex, working with material, such as brick colours, that fitted well together. 'They've approached the project with great sensitivity and vision,' says the gallery's curator, Hugh Allan. 

At 37,000 sq ft, the gallery is expansive, its display rooms specifically spanning two levels and four of the five buildings. Three of them were existing structures, listed old scenery painting studios that were purpose built in 1913, which the architects refurbished for the new gallery's needs. They used to be dramatic, single-height spaces and after Caruso St John's intervention, while the space is now divided into two levels, a subtle drama remains, with tall ceilings and light flooding in from large openings on the sides. 

'The [original] spaces were too big to be used as galleries,' explains Peter St John. 'Now, there is a lot of flexibility in the scale and arrangement of the galleries.' These historical buildings are book-ended by two new builds - a striking saw-tooth, corner one, which marks the complex's main entrance and way to the café, and a slim structure at the end of the row, housing the gallery's office space and dedicated shop. 

Three sculptural, white engineering brick staircases connect the different floors and buildings inside, featuring a smooth timber handrail on one side - made at the same German manufacturer Caruso St John used in their Tate Britain project - and a cast concrete one on the other, cleverly appearing to be carved into the wall. 'It is about making stairs more than just being perfunctory and providing a means of escape; they also make the building more expansive and public,' explains St John.

This is certainly a busy week for the East London practice. Their Gagosian Gosvernor Hill project throws open its doors in a couple of days, as does their Liverpool Philharmonic; a sensitive refurbishment and expansion of the 1939 grade II* listed concert hall. 

Newport Street Gallery is the first to launch in this series, opening to the public today - although its fittingly pharmacy-themed café and restaurant will not be serving till 2016. Newport Street Gallery's inaugural exhibition will be 'Power Stations', a solo show of work by John Hoyland (1934-2011); the first one since the artist's death.