“Can you make it clear I’m not a Hackney deserter?” Will Farquarson pleads at the end of our interview. “I want them to know I was forced. You can blame it on my girlfriend.”

He’s quite insistent. While the rest of his band have long been south Londoners, Farquarson resisted the urge for as long as he could. Ironically, when the Bastille musician finally left his home near the Pembury Estate for Clapham at the end of last year, it was simply to suit his girlfriend’s work schedule – not because he wanted to splash out with the spoils of a number one album.

By all accounts, 2013 was a mammoth year for Bastille. In February, their single Pompei exploded onto the scene (sorry), firing them to number two at the summit of the UK singles charts (very sorry).

A platinum-selling album, Bad Blood, followed and if anything this year is just accelerating the momentum.

When I speak to Farquarson, who plays bass, guitar and keyboards in the four piece, he’s just returned from America, following stints on the Late Show with David Letterman, Jimmy Kimmel Live! and Saturday Night Live.

“At first, it was pretty daunting,” the 30-year-old admits, “but then we realised Leonardo DiCaprio was also appearing on the show. Suddenly I wasn’t worried about our performance – he was being done up in a dressing room a few doors down from us, so my focus just turned to following him around the whole time.”

Was it a successful mission? “I said hello at the end of the show, where they have this kind of big hug thing. He was pretty relaxed about it all, seemed a nice guy.”

If their breakthrough in Britain was unexpected, it’s fair to say Bastille’s success in America shocked them all ends up.

“It’s unfathomable,” Farquarson adds, acknowledging that even bands well established in Europe can take years to make the same impact across the Atlantic.

Brits nominations

Next week, however, it is all about the Brits. Bastille’s melodic, stadium-friendly pop has won them nominations for no less than four Brit awards – British album of the year, British single, British group and British breakthrough artist.

Do the band feel they have a chance?

“Well, we’re up against the Arctic Monkeys for British group and David Bowie for album of the year, so we can immediately rule those ones out.

“To be honest, we never expected to be nominated for anything – we’ve never even done an awards thing before, so it’s always a surprise.”

As it happens, Farquarson actually seems to be rooting for one of his British breakthrough award rivals. “Laura Mvula is amazing. Her album is one of the best things I’ve heard in ages. I met her the other day – before, I’d just tweeted her a couple of times – but I was really drunk so just started shouting, ‘Laura, Laura, it’s Will!’

“She was very confused at first, but eventually I managed to explain who I was and we had a great chat. She’s such a genuine person and yeah, I do hope she does well.”

Much like Mvula, Bastille’s recent success has come through gradual momentum. They formed in 2010 after initially backing the band’s singer and songwriter, Dan Smith, who was performing as a solo act.

“Dan was quite self-depreciating, and began to feel a bit embarrassed saying ‘We’re the Dan Smith band’.So we turned it into a more traditional band dynamic, and that’s when we thought we’d get Kyle [Jonathan Simmons] in to make it a proper group.”

While Smith still remains the face and spark behind Bastille’s songs, the band have begun writing a second album and Farquarson believes their composition is noticeably more collaborative. With the band’s increasingly tight schedule, he reveals that most of this material is now honed during soundchecks: “Apparently it’s what Hendrix did. It’s nice to get back to that old-school style.”

The band are certainly expanding their sound – “some songs will have a heavier, grungier edge like Nirvana, there’s some late Nineties R&B influences” – and with an already global audience, the anticipation for their next release is palpable.

With so many eyes on the quartet, Farquarson admits that he has a knack of getting noticed at the most inopportune moments.

“For example, the other night I was in the McDonalds in Clapham with my girlfriend at about one o’clock in the morning. It was at the end of a night out, I was looking pretty dishevelled and one girl suddenly asked if I was that guy from Bastille. I always find myself saying ‘Yeah, but I don’t usually look like this’.”

The rock’n’roll lifestyle has its advantages of course. Farquarson points out that he’s travelled to more places around the world than he could have ever hoped for, and even when he had a rare moment of downtime around Christmas, he found himself itching to get back out on tour.

It’s lucky Bastille seem to have enthusiasm in abundance, because, one year since Pompei, the hype still shows no sign of cooling down.