A self-employed builder who struggles to hold down a job for more than a month used a chance meeting with Ed Miliband to highlight his concerns about job instability.

Robert Quinn approached the Labour opposition leader halfway through his visit to Camden Town to talk to independent business owners about his party’s plans to freeze energy prices and cut business rates.

The 34-year-old builder told Mr Miliband that he has been in and out of the Jobcentre for years looking for work fitting air conditioning systems, often coming out of the centres in tears.

Despite working on the Emirates Stadium and the Royal Festival Hall, he has never been able to keep a job for long because he says that employers exploit loopholes so that he is never kept on for an extended period of time.

“I’ve done the air conditioning in the Royal Box at the Royal Festival Hall, at the Emirates Stadium, at the Millennium Dome, but the longest I’ve been able to work is a month-and-a-half,” the Hackney resident said.

“I’m trying to be a man and not be a criminal, but sometimes I just want to do what other people do and find a flat and grow weed in it. But I’m not taking the easy way out.”

He criticised the coalition government for ignoring the problem of job instability in the construction industry, as a large crowd of shoppers gathered in Camden High Street to watch the exchange with Mr Miliband and shadow business secretary Chukka Umunna last Thursday morning.

Some laughed while others took photos and videos of the spontaneous discussion outside newsagents Camden News.

Mr Miliband had visited the newsagents to talk to the owners about his Labour Party conference pledge to freeze energy prices and cut business rates.

Mr Quinn happened to be visiting the newsagents as the opposition leader arrived.

Mr Miliband also met Miguel Martin, who has run Martin’s Butchers in Camden High Street for 17 years, and Beresford Casey, co-founder of Haché Burgers, Inverness Street, to discuss Labour’s policy.

The 43-year-old leader of the opposition, who lives in Dartmouth Park, said after the visit: “Energy costs and business rates are massive, massive issues.

“It was really moving meeting Miguel because he’s been there 17 years, he loves Camden, he says he is the only independent butcher around there and he really feels his business is on the margins.

“I think people are asking, ‘When is someone finally going to stand-up for us and do something about it?’ That’s what we are going to do.”

He also met with entrepreneurs from the Camden Collective, which provides a work hub for business people.