National Portrait Gallery’s renovation has created a beautifully public-facing museum

Squeezed between the imperial kitsch of Trafalgar Square and the tourist kitsch of Leicester Square, the National Portrait Gallery is itself a museum perched between two periods, two worlds and two ideas of what an art gallery might be.

Like Trafalgar Square, the NPG has a mission to represent a version of British history; like Leicester Square, it is endlessly reinventing itself in the shifting sands between celebrity, culture, culture wars and fashion. This is a building that is constantly being rebuilt, with extensive interventions by architects including John Miller, Piers Gough and Dixon Jones over the past few decades. None has quite solved the problems. Will the newest have any more success? After all, the gallery’s mix of monarchs and models, pop stars and proto-feminists now looks, perhaps rather surprisingly, remarkably modern.

This newfound approachability has been hugely enhanced by a £41mn refurbishment and some surprisingly radical, if careful, changes by architects Jamie Fobert and Purcell. The biggest change has been to flip the building around so that its entrance is now where it always should have been, looking towards the little piazza and up Charing Cross Road, rather than the rather eccentric little lobby which curiously ignored its imposing Italian facade.

The architects have cut new doors into the arched windows of that palazzo facade, designed by the original architect Ewan Christian and opened in 1896. If it sounds a little drastic, it doesn’t look it. In fact it has been done so delicately that it looks as if it was always this way.

The municipal stuff, the council flower beds and iron railings around what is now the new entrance, have been cleared away to create a broad, generous public plaza characterised by grey granite, which makes it look like part of the streetscape rather than a private forecourt. A statue of actor Sir Henry Irving has been shunted over to give more space and now looks, appropriately, towards a theatre. Chunky granite benches make it yet more public and, in an area renowned for rough sleeping and antisocial behaviour, it seems a refreshingly generous move. Everyone should get something from art.

Those new openings now feature three tall bronze doors, each one inscribed with a grid of female faces by Tracey Emin. Their squiggly, slightly angsty style seems to emphasise the creases on their complexions, the lines and the worry. Betraying Emin’s almost secessionist stylings, these apparently began as homages to famous faces but became representations of women in general (with one exception, marked “Mum”). It’s an early indication of the fierce attempts being made to redress the museum’s balance of representation.

The new entrance is a very different kind of space from the tight, vertical lobby of old. Generous, airy, light, perhaps a little bland, it refers to history in, for instance, its subtly patterned marble floor, which echoes the original white mosaics (and also adds a little Italian Modernism in the process). Striking here also is a small crowd of busts and sculptures mounted on an array of plinths designed by architects Nissen Richards, who were responsible for the exhibition design throughout. It populates the otherwise slightly blank space to just the right extent, encouraging visitors to wander in through those bronze doors. A new gallery beside the old renovated escalator draws in visitors with walls of new acquisitions, some superb, others truly ghastly.

Inside the museum, much has changed and much has been retained, with around 1,000m sq of new gallery space being found or created from existing spaces — old areas that had been underused or, bizarrely, forgotten. These include a bow-windowed room looking towards the church of St Martin-in-the-Fields which must, surely, have been one of the finest spaces in the museum but had lain fallow as empty offices. Another striking space now features Marc Quinn’s “Self” alongside a blood-red wall of haunting death masks. A new vertical connection in the form of an elegantly wrought stair leads down to the vaults, repurposed as a series of surprisingly light education spaces and a bordello-style bar which will be open after hours and which, Fobert is very quick to tell me, was nothing to do with him.

A new ground-floor bookshop was designed by Alex Cochrane Architects, more open and expansive than the former store, in light colours and canary yellows. There are more new galleries upstairs, airy and different in feel from the heavier historic rooms, which Nissen Richards have repainted in bold and sometimes surprising colours, ranging from aubergine to an enfilade of vivid pillar-box red, claret and green, which is almost filmic in its effect.

Where windows were blocked up they have been liberated, introducing revived views; rooftop lanterns now admit the wonderful toplight they were always meant to. The more historic rooms are architecturally mostly unchanged but feel more vivid, even if some of the stultifying portraits of great men continue to, well, stultify.

A little more interpretation, diversification and politicisation work nicely here. Most notably it all comes together in Joshua Reynolds’ magnificent 1776 portrait of Mai, recently acquired jointly with the J Paul Getty Museum for £50mn. It sits in the centre of one wall facing a small self-portrait of a very young Reynolds, holding his hand to his brow as if to peer into the distance — at Mai, perhaps. It is a poignant dialogue, the gallery highlight. The portrait of Mai stood in Reynolds’ studio until he died in 1792; he seemingly could not let go.

A visitor to the revamped gallery might wander in and notice not that much different. This is a quiet, subtle and sensitive series of complex interventions, and much of the work, from new wiring and services to the restoration of original finishes, floors and woodwork, remains discreet. Apart from that singular spiral stair with its slightly flashy steelwork balustrade and a couple of interior mis-steps in the garish bar, there are no look-at-me acrobatics here, just solid, fine museum design with the visitor and the works rather than the architect in mind.

There is a notion that this was never a museum of great art, rather a collection of famous faces, but the breadth of the collection becomes clearer here, from wonderful photos to shifty Tudors (now vividly lit behind new metal box frames), from panoramic new works to intimate studies. Renewed and made more public, becoming more a part of the city and generous in its embrace, it presents a serious challenge to the National Gallery next door.

Opens June 22, npg.org.uk