Melanie Onn, the Labour MP for Great Grimsby and new shadow housing minister, grew up in the town she has represented in parliament since 2015. Onn, who worked in Labour’s compliance unit for 10 years, is friendly and chatty and seems to have a deep and genuine interest in the town. “I was born and raised in Grimsby and moved around a lot within the town when I was younger,” she says. “Some people want to just be an MP, and that’s fine, but I really wanted to represent the town,” she says.

Onn, 38, lived on two local estates, and describes herself as “born and bred social housing”. She has also experienced youth homelessness. Aged 17, while living with her aunt, they had a falling out, and she ended up turning to local charity Doorstep for support. It provides accommodation for 16 to 25-year-olds in Grimsby and neighbouring Cleethorpes. “They put me in a house with girls of a similar age, who’d had similar family breakdowns. It was a lifesaver, because it was a really tense situation,” Onn recalls.

The charity still works with young people who find themselves in difficult situations. But Onn thinks that both the charity and the individuals they help find things much harder now. “They are facing some significant challenges. Times are tough: their target group have less money in state support and they are becoming increasingly squeezed,” she says. “One of the first things my support worker did was help me apply for benefits – and the availability and security of the benefits going straight to the landlord was helpful. But it’s nigh on impossible for young people to get that kind of support now.”

Despite having strong credentials to be shadow housing minister, Onn says the appointment in early July was “unexpected”. Part of the surprise comes from Onn’s own recent past in the Labour party. Shortly after Brexit, she resigned as deputy leader of the Commons, criticising Jeremy Corbyn’s leadership. She has also said Corbyn has a “woman problem”. In the 2015 Labour leadership election, she nominated Yvette Cooper. Has her opinion shifted?

Melanie Onn says that empty homes in Grimsby need to be compulsorily purchased. Photograph: Christopher Thomond/The Guardian

“We did a lot, lot better in the election than we expected, and I think he’s now earned the right to be leader of the Labour party and take his programme forward,” Onn says. “We’re in such a good position to put pressure on the Conservatives now, with a hung parliament, and so I felt I had a responsibility to try and help the Labour party in that endeavour.”

Onn’s portfolio, working with housing secretary John Healey, particularly focuses on homelessness, sheltered housing, private renting and home ownership. “There are different issues across the country. Can people who are renting afford to get on the housing ladder? Can people in Grimsby get secure accommodation, and the right kind of accommodation?” Onn says empty homes in the town need to be compulsorily purchased, tenants need better rights and longer tenancies, more social housing is needed in cities, and better social housing for people with disabilities and older people is an urgent requirement.

As we wander around Grimsby, the differing issues in housing in the town are stark in comparison to London: private sector empty homes are an issue, affordability generally isn’t, and some nearby tower blocks that have fallen into disrepair are being demolished as the housing association says they are too expensive to refurbish, which not all residents are happy about. “There’s been a big increase in housing issues in my caseload, not just because people have clocked my new role. There are issues around private rent, usually to do with quality and security of tenure. If people have been on housing benefit, the landlords aren’t overly forgiving when they build up arrears. In social housing, the problem is we don’t have enough of the right kind of stock: lots of people want adapted, accessible properties, or smaller properties to downsize to,” she explains.

“A lot of people have just continued to pay the bedroom tax and a few people have been moved to smaller properties by housing associations. But we had around 700 people fall into arrears quickly. Homelessness is increasing, and becoming more noticeable: some of it’s about housing in Grimsby but some of it is about dependency – and lots of people here have been in the [armed] services.”

At this point, a passing woman interrupts, to thank Onn for sorting out a problem with the Jobcentre, saying her benefits were reinstated within a week. “I didn’t set that up,” Onn says embarrassed. Onn’s seat sits within North East Lincolnshire, which had the 10th highest share of the leave vote in the EU referendum. Onn voted to remain, as did the local Conservative candidate. “A lot of it was down to the fishing industry. There were lots of jobs in the past. In the 60s, 70s and 80s, you could go down to the docks and get a job really easily, but you simply can’t now. Ukip capitalised on that, but offered no answers themselves,” she says. “And there was immigration.” But she believes that during the election “people were concerned about the NHS and public services, not immigration.” If elected to government, Onn says, Labour would scrap the bedroom tax, reinstate housing benefit for under-21s – which helped Onn when she was homeless – and concentrate on building both social housing and homes for people looking to get on the property ladder. “We need to have big ambitions on housebuilding and tackling the housing shortage. The Tories talk a really good game, but haven’t built the numbers they said they would.

“They’re not keen on talking about social housing as a solution. People are starting to ask questions: why is so much housing benefit going into the pockets of private landlords when it could be reinvested into long-term housing stock? We could build the kind of homes people want.” Six red brick and concrete blocks dominate the Grimsby skyline. The housing association that owns them claims they are too expensive to refurbish: the towers are unclad, in disrepair and with poor insulation. An older woman on a mobility scooter approaches Onn and says, “I lived there. I’d move back tomorrow. I loved it. I hate where I am now.” She says she was moved out against her will when the demolition was announced. Onn says many residents were unhappy with the move. She tells the woman that her grandmother lived there too, pointing up to a balcony she played on as a child. It’s clear that the housing crisis affects North East Lincolnshire too.

Curriculum vitae

Age: 38.

Lives: Grimsby.

Family: One son, aged 10.

Education: Healing comprehensive, Grimsby; Franklin sixth form college, Grimsby; Middlesex University (Politics, International Studies and Philosophy).

Career: 2015-present: Labour MP, Great Grimsby; 2017-present: shadow housing minister; 2016-17: member, communities and local government select committee; 2015-16: shadow deputy leader, House of Commons; 2015: member, energy and climate change select committee; 2010-2015: regional organiser (Yorkshire & Humber) Unison; 2001-2010: several positions from receptionist to head of compliance at the Labour party.

Public Life: 2008-2010: Labour party representative to electoral commission, MoJ, ACPO; 2002-2007: GMB union branch secretary and staff representative.

Interests: Running, trying to keep pets and house plants, yoga, karaoke, new house projects, holidays.