And before you ask, no, I’m not going to retire.” You can forgive the preemptive strike. Richard Rogers, Lord Rogers of Riverside to give him the grand title he rarely uses, has fielded a lot of questions about the “r” word lately. The young Turk who gave the world those once futuristic, still shocking buildings with their guts hanging out – Paris’s Pompidou Centre, London’s Lloyd’s Building – nowadays, at 74, looks like nothing more radical than your favourite grandpa, the one with the twinkly eyes and endearingly rambling tales about the war – the war against the Prince of Wales, architectural conservatism and cities gone to the dogs.

He’s reached “that retrospective time of life” – later this month a massive exhibition of his life’s work opens at the Pompidou, marking the building’s 30th birthday – so “they expect you to pop off at any minute”. Rumours mounted after a remarkable year so backed up with plaudits – the Stirling Prize last autumn for his Madrid airport, the Pritzker Prize, and the Venice Biennale’s Golden Lion, for starters – you half-wondered if the juries had got wind of his imminent demise. Final proof? Last year, the name of the firm he established 29 years ago, Richard Rogers Partnership, was changed to Rogers, Stirk, Harbour and Partners, to honour the next generation of young Turks – Ivan Harbour and Graham Stirk – increasingly taking the reins. Slippers and cocoa seemed certain. “Can you imagine?” he breaks out into one of his guffaws, as if the very idea was the most ridiculous thing in the world. “Which it is.” That’ll be a no then. “

I enjoy life too much,” he says. And Rogers really does seem to have a lovely life. His place in history is guaranteed by the Pompidou and Lloyd’s. He still has fulfilling work – more than ever, with Heathrow’s Terminal 5 opening next spring, a City skyscraper, Leadenhall Building, in the offing, and his largest building to date, the Javits Centre in Manhattan, on the drawing board. It’s a buzz of activity in an office which, a few years previously, seemed in hiatus compared with that of his friend and eternal rival, Norman Foster.

His treasured roles as Ken Livingstone’s adviser and Labour peer mean he is still hard-wired into politics, taken seriously. There’s the big artsy family: still on good terms with his first wife Su, five sons all in influential, creative, fulfilling jobs (one, Abe, has designed the exhibition). There’s the lovely office by the Thames in Hammersmith, filled with 180 reverential staff. And, icing on the cake, there’s having the River Café for your staff canteen just by the front door. The cherry on top? Your wife, Ruthie, runs it! Extra portions of chocolate nemesis all round!

With nearly 50 years of hindsight poured through the exhibition, his life’s work seems less about architecture than selling this Pollyannaish, liberal lifestyle to a mercenary, puritanical world. Born to creative, professional, left-wing Italian parents who escaped fascist Italy for Britain in 1938, his view of life is distinctly Italian – “Where public life and family are entwined,” he says, “as long as I was sitting at the family table everything was OK. I was very affected when I was 5, in Florence, and I’d look across the street and see this café, and every morning I saw what I assumed was an accountant, who’d come in, they’d put a table on the pavement, they’d give him a phone, and he’d do his job. And I thought that’s what I want to do. Not to be an accountant, of course. But the idea that you could mix in your lifestyle, your work, your city, your quality of friendship.”

His wish came true. There are few architects who live the worlds they espouse quite so wholeheartedly as Rogers. Foster – with whom he started in business in the early 1960s – may now have the thousand-strong design-factory, but Rogers, you suspect, has the nicer life. Rogers’s high-tech, drenched in old-fashioned modernist optimism for this thing called “society”, has soul and colour, Foster’s has rigour, but no passion. Indeed, once you get past the shock value of his eviscerated buildings, Rogers’s architecture isn’t really about looks at all. He despises the word “style”, instead his buildings – and this is what was so radical about Pompidou – are basically big family tables, public spaces in which people come together arguing, sharing, resolving differences, given form by the life inside. His vision for cities, now applied patchily as government policy, is all about public space, generosity, tolerance.

Not everyone has shared the Rogers vision: the architecturally conservative, for instance will never warm to his Heath Robinson buildings. There are those who quite rightly state that his “guts on the outside” aesthetic was never very practical (he hasn’t used it himself in a while).

Last year his support for Palestine nearly cost him the Javits job in New York. “The office constitution states you have to think before taking on work which is antienvironment, military, and so on. But then people say ‘airports?’ In that case, since an architect alone cannot stop airports being built he should make them as good, as environmentally sound as possible. But it’s a difficult excuse to make. All architecture is political. All work involves debate, compromise. You’re always juggling, questioning yourself.” This is what makes him unique in Britain, where architects, eyes on realising their monuments and plumping the bank balances tend, as far as possible, to eschew politics.

Rogers marched for CND in the 1950s, against Bush in the Noughties. When Margaret Thatcher started dismantling the public realm so dear to him, private politics became professional. The crux came while designing “London as it could be”, highlight of the Royal Academy’s 1986 exhibition, Foster Rogers Stirling, which envisaged London as a Thames-side playground – fantastical at the height of the no-such-thing-as-society era. Thereafter, building took a backseat to campaigning for Britain’s “urban renaissance” through the Reith Lectures, new Labour’s Urban Task Force, battling with John Prescott, and, today, Livingstone. He concedes that he is somewhat on his own: “I do sometimes feel like an eternal refugee.”

When he arrived in 1938, “there was only one espresso machine in London”. Now, he thinks, we’re at last starting on the right road towards civilised life and decent coffee for all. . . Pollyanna again? “There are a lot of big ifs: the distribution of wealth is horrific. But overall, what an evolution – life is a lot better, especially for those of us who are more fortunate. For those who are not, life is tough. But what can an architect do for them?” his voice trails off. “I don’t know... ”

Richard Rogers + Architects, Pompidou Centre, Paris (www.centrepompidou.fr 00 331 44 78 12 33), from Wed, until March; the exhibition moves to the Design Museum, London SE1, in April

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