Sebastian Faulks is tired. At least, he says he is. In a quiet corner of the Shelbourne Hotel in Dublin, he orders tea and sinks into the plush depth of one armchair while propping his feet on another. Not much else gives the impression of fatigue. He claims incoherence, but is articulate and demonstrates the amicable integral to the characters in his novels.
Dublin comes at the end of a month-long, if-this-is-Tuesday-it-must-be-Leeds tour of readings and interviews for Faulks, who is on the publicity circuit to promote On Green Dolphin Street, his novel. The book marks a departure from the world of his French trilogy The Girl At The Lion D'Or, Birdsong and Charlotte Gray. Published in 1993, Birdsong vaulted to the top of the best-seller lists and made him famous.
"I got started writing novels in the 1970s," he says. "I wrote several novels before I got one published. And I expected the normal run, selling 2,000 hardback, 20,000 paperback. I never expected the success of Birdsong. "With On Green Dolphin Street, "the idea for the period came first", Faulks explains. The narrative extends across 1960 and the continental US. Jetting between Washington DC, New York, the Midwest and California - with the odd detour to Europe - the main characters, caught in a painful love triangle, work through the tangle of their lives during the uneasy peace of the cold war.
Despite the anxiety, this is the golden age of the US, its lifestyle, cinema and music creating an image of ease, luxury and fun that had the rest of the world salivating with envy and longing. "Nineteen fifty-nine was the first year I remember being alive; I was six. The book was a journey back for me."
His experience as a journalist helped shape him as a writer, even though "the novels came first", not the reporting. He interrupted a successful career, leaving his position as literary editor of the London Independent "10 years ago almost to the day" to write full time.
"I thought I would give it three, four years. I certainly didn't expect it to last longer than that. Journalism taught me how easy it is to find things out," he smiles. "You just get on the phone and get the information. I'm essentially a shy person, but you learn how to do it."
A research assistant in New York, his own trips to the US - he covered the 1984 presidential election - and the Internet took care of the remaining detail. "The hard part is recreating the sense of the time, the mood, the way people felt."
It took Faulks a calendar year to write On Green Dolphin Street. He worked daily from January to December, keeping to a schedule. "I have a bad start to the day," he admits. "It takes me an hour, two litres of tea and the morning papers before I can get going. After this, I go to my studio - I have a room in a friend's house not far from home - and I get there about 9.30. I read what I've done the day before, then work from 10 to two. Then I go home, have lunch, get a snooze if I'm lucky, then work again from five to seven. It's as if you were doing your university finals every day for a year. Of course, there's not the same kind of pressure. But there is the same kind of intensity."
So why does Faulks subject himself to the trouble of writing? "Because I would be very unhappy if I didn't. There is a section in On Green Dolphin Street where Mary and Charlie are on holiday in France, and he talks about why writers write. I was being a bit simplistic with it there, but really, that is why you write. This texture of life is not satisfactory. In writing, you put a meaning and order and value into existence."
His immersion in the story also has its recreational value, however. "At night, when I'm lying in bed, or in the bath, I could switch off wondering whether the plumber would ever arrive [he's having work done on his house], and become my characters." He closes his eyes. "As Mary, what am I going to wear? How will I react in this situation, what am I going to say? Or as Charlie. When it's going well, you just slip into these people. That's a lot of fun."
When he's not working or wondering about his characters, he clears his mind with sport. "It's my main relaxation. I watch a lot of sport, and play tennis and golf. I like going skiing: it's a brilliant way to empty your head. While you're going down that hill you have to concentrate hard on not killing yourself. And I can also turn off in a game of golf, by concentrating hard on hitting that stupid little ball - or, in my case, looking for that stupid little ball."
The acclaim for his previous books has captured much attention for the new work, not to mention the scrutiny of critics gleefully poised to pounce on the slightest weakness. Faulks doesn't let the background noise of the reviewers, or their "cavilling" on about details, bother him.
"I don't read reviews. I didn't like Billy Elliot, and the man sitting beside me did. We can both give reasons for that, and they are all valid. What matters is the depth of people's response to my books. People will come up to me, for example, after a reading or to get a book signed, and tell me the book has touched them deeply, changed them somehow. This is what's important."
Does Faulks have a goal for the future? "I'd like to write a really, really good book," he says. Isn't that what he's doing at the moment? But no, Faulks is looking for something more ethereal. "I write realistic novels, and that's a choice. I'm not fond of magic realism or science fiction. But I would like to write something that pushes edges so far that something transcendent happens. I want to work with death and time, bring those themes into a book. I want to bend the idea of time while remaining realistic."
His mouth twists into a sardonic smile, his blue eyes gleam. "I might call it The Plumber Arrives." For now, however, his plans are more concrete. "I'm working on my golf handicap," he grins. But then he switches tone, to polite gravity. "I have a germ of an idea, but it's not really developed yet, just a germ." If, as a journalist, Faulks were writing or commissioning this story, what aspect would he concentrate on?
"You know, no one ever asks about the words. People ask about plot, character, setting, history, but they don't ever ask about the words. For example, Miles Davis. His finger work is what sets him apart, but nobody ever talks about that. Or you discuss Picasso, his paintings, but nobody ever talks about the brushes he uses, or the paints, or canvas. And that's what writing is. It's all about choosing the words, why this particular one and not the other. These are what make up the novel - or the music, or the painting. This is the essence."
On Green Dolphin Street is published by Hutchinson, £16.99 in UK