Another surprise is that the "my arse" layabout Jim Royle in BBC comedy The Royle Family was once a skilled tradesman, a plasterer who served a six-year apprenticeship. Thirty years since he was forced to put down his plasterer's float, it is still in the bone. It is a source of pride to him that the firm he worked for from 1955 to 1961 demanded high standards from its tradesmen. Tomlinson is enraged by contractors that allow unskilled workers to botch jobs and short-change customers. He still has the unforgiving eye of a professional and his conversation is peppered with comments about the importance of standards.
Now, sitting in the Savoy Hotel in central London at the start of a two-month publicity tour for his autobiography, he delivers a short lecture on fibrous plastering and monolithic flooring. "In the hallway you will see a fancy fluted ceiling and Corinthian caps on top of the columns. That's fibre. They are cast out of a mould. Adams Brothers, where I served my time as an apprentice, was probably the premier firm in the north of England for that kind of work. They did work on cathedrals and churches and specialist buildings. We learned a lot – not just ordinary plastering and stuff."
He took his intermediate City and Guilds qualification at Walton Technical College in Liverpool at the age of 15 in 1954 and completed it when he was 17, going to night classes along with one-day release from Adams. Even now, despite the fact that he must be nearly a millionaire, he fills some of his spare time between acting and script-writing skimming walls and knocking up extensions for his nearest and dearest.
So what led him to break out of the conservative mould of the skilled operative? Nothing in his background suggested rebellion. He was brought up in a true blue Protestant family, and even joined the National Front after Enoch Powell's "rivers of blood" speech in April 1968, only leaving in 1972. Even then he didn't start reading The Guardian – far from it. Several fellow union activists were shocked by his right-wing views as they picketed together after the start of the first national construction industry strike in June 1972. One or two even claimed he was a police spy.
So why did he get involved in the strike that led to his jail sentence? "The conditions on the motorways we were working on were appalling, absolutely appalling. There were no facilities. If there were toilets, which was a rarity, they were filthy, blocked and not working, or they were miles away. So if the lads wanted to go to the toilet they just had to go into the middle of the field, or if they were lucky, squat behind a bush. There was one guy who cut his head in a ditch and wouldn't get it seen to till dinnertime because he didn't want to lose his job. That was the norm.
He was brought up in a true blue Protestant family, and even joined the National Front after Enoch Powell’s ‘rivers of blood’ speech in April 1968
"Then there were the little huts for the men in the middle of the field or on the sides of the road. Sir Alfred McAlpine wouldn't have been allowed to put any of his racehorses in them. He wouldn't have been allowed. He would have been prosecuted if his horses had been kept in the same conditions as his workers."
Tomlinson sees a key problem at the time as the "lump", a system under which a man was paid a lump sum, without deductions for tax and National Insurance, on the understanding that he was self-employed and therefore not the company's health and safety responsibility. Inevitably this led to a decline in professional and safety standards.
Tomlinson gives an example: "A house is probably the single biggest item that a young couple will buy in their lifetime. But the drains and stuff could be put in by someone who has never been on a site before, who doesn't know what a drain is, who doesn't understand the importance of the fall from the bottom of the down spout to the drain. It's got to be at a proper pitch so all the silt is taken away. I've seen fellas come on to the site who have worked in offices, been bus and tram drivers, and right away been putting to work with lads putting in the drains. And they haven't got a clue."
On 6 September 1972 Tomlinson and others took a "flying picket" to seven sites in the Shrewsbury area to persuade and cajole groups of construction workers to join the strike. The following February, Tomlinson and 23 others were charged with a variety of offences including affray, unlawful assembly and damage to property. More importantly, several of them faced a charge under the 1875 Conspiracy and Protection of Property Act, which had never been used before and carried a life sentence. The gist of this was that a group of them had got together at the Bull and Stirrup public house in Chester to cause mayhem.
Tomlinson has believed ever since that this was a politically motivated show trial cooked up by the Tory government and the major contractors. He made this point in court after he was found guilty on 19 December 1973, saying: "I look forward to the day when the real culprits – the McAlpines, Wimpeys, Laings and Bovises and all their political puppets – are in the dock facing charges of conspiracy to intimidate workers from doing what is their lawful right – picketing."
Tomlinson survived the next 19 months until his release in July 1975, after a noisy national campaign in support of him and Dennis Warren, the other member of the "Shrewsbury Two". How did he survive jail and the inevitable blacklisting that followed? "You just have to get on, haven't you." Does he suffer nightmares about it all? "Bloody hell, no."
One or two good things did happen to him in prison, however. First, he discovered Radio 4, and is still a big fan. Second, he was introduced to the "building worker's bible" – The Ragged Trousered Philanthropists, Robert Tressell's 1914 novel about the lives of a group of painters and decorators in "Mugsborough" – while in Leicester jail. He still loves it for being true to the life that he knew.
"I've seen lads working in the rain from eight o'clock in the morning until six at night, even on dark winter nights, exactly like in the book," he recounts. "Soaking wet, soaking wet, but wouldn't stop. The foreman would be standing in the site hut watching them, in the warm, in the dry, with a cup of tea, making sure they didn't get out of the trench."
He says moves are afoot to turn the book into a film: "Yes, I had a call from Andy Serkis – Gollum in The Lord of the Rings – who's been nominated for an Oscar. He is a good friend. He asked me if I fancied a role."
A dynamic 64-year-old, Tomlinson certainly doesn't have the worries that Lennon and McCartney put into the mouth of their putative pensioner. When he married his second wife, Rita, in January, the event was sponsored by Hello! and OK! magazines. Rita, a former social worker who now acts as his agent, explains that they are only at the Savoy now because the Waldorf wasn't acceptable (transparent en-suite toilets, apparently).
I’ve seen lads working in the rain from eight until six, even on dark winter nights, soaking wet, soaking wet, but wouldn’t stop. The foreman would be standing in the site hut watching them, in the warm, in the dry, with a cup of tea, making sure they did
"All the Americans complain about it," says Tomlinson.
After a modest start in social conscience films in the late 1970s, he landed the role of trade union official Bobby Grant in Channel 4's Brookside, joined the police alongside Robbie Coltrane in ITV's Cracker and then achieved superstar status with the Royles. Now he has reached the sunny uplands of success: a catchphrase, an £800,000 advance for his autobiography, the title role in the 2001 film Mike Bassett: England Manager and now a television advert for British Gas. Offers of acting and scripting jobs are flooding in.
But he still frets that money will rot his Liverpudlian working-class roots (he worried that the intercom would corrupt his soul when he moved into a warehouse conversion) and bristles when the photographer asks if he had more than one house. Instead, he and his wife are splashing out to replace the 50-year-old caravan he has at Benidorm in Spain.
Ricky is published by Time Warner Books, £12.59.