April Matlala, who lost most of his home to a fire three years ago, got a big surprise when he saw who was moving into the shack next door. The new residents of Mamelodi, an impoverished township near Pretoria in South Africa, were young, middle-class and white.

"They wanted to experience a different culture from where they're living," reasoned Matlala, 44, pressing the neck of a beer bottle to his lips. "In South Africa we have about 11 cultures. If you don't experience all of them, you're not a real South African."

Julian and Ena Hewitt, both 34, and their daughters Julia, four, and Jessica, two, left their four-bedroom house, livestock and swimming pool in a gated community to move just seven miles (12km) down the road into a 3m x 3m (10ft x 10ft) shack with no electricity, a communal water tap and a pit toilet. They stayed there a month, living on 3,000 rand (£189), the average income of a black family, and blogged the experience.

Their August sojourn in a "new country", as they put it, has been lauded as a brave attempt to cross racial divides and draw attention to the savage juxtaposition of rich and poor in South Africa. But it has also led to accusations of self-serving "poverty tourism" that could offer only superficial insights into black township life.

The Hewitts, who are well-travelled and used to roughing it, got the idea from India where two young professionals spent a month living in poverty on the premise that "empathy is crucial to democracy". Ena, an estate agent, said: "If you can't have empathy and understanding of how your fellow man lives then it's impossible for this country to move forward. We want our girls to grow up here, not in the UK, so we want them to know and understand the realities of this country."

The Hewitt family and neighbours make beer in the Mamelodi township near Pretoria. Photograph: Jordi Matas for the Guardian

Nearly two decades after racial apartheid bit the dust, its legacy persists in spatial segregation between affluent suburbs and neglected townships, with millions of black people still commuting from the latter at great expense of time and money.

"It's just so easy to live in a bubble in South Africa and especially for the middle- to upper-class to build higher walls rather than building bridges," Ena continued. "This is a way to create empathy, a way to build bridges and a way to see how the majority of this country lives. It really is very easy to be oblivious of it.

"What's caught us off-guard is the media attention this thing has generated. It shows the serious disconnect that's still there. There are probably more tourists who've been in townships than white South Africans. Hopefully this is something that other people can look at and say, 'Well, if they stayed there for a month, we can at least go visit and see where our domestic worker lives.'"

The Hewitts chose Mamelodi to be close to their own domestic worker, 50-year-old Leah Nkambule. One afternoon a small group gathered on plastic chairs outside her home tending a cooking pot above a wood fire. Nearby was another shack structure containing the Hewitts, two other tenants and their landlord, who rises at 4am each day and walks more than two miles to catch a train to work. Beyond them was Matlala's single-room shack, then one taken over by drug dealers.

The Hewitts read with neighbours inside their shack, which had no electricity, a communal water tap and a pit toilet. Photograph: Jordi Matas for the Guardian

The Hewitts' spartan home (rental of 170 rand (£10.70) a month) was made of a corrugated roof with metal sheets on the sides. Among the contents were mattresses on the floor, a plastic basket of clothes, children's shoes, a roll of toilet paper, a kettle on a paraffin stove and an iPhone devoid of battery life. Outside was a small lawn fenced from a dirt track by barbed wire held up by posts fashioned from branches. Children played merrily with Julia and Jessica then helped Julian hoist a piece of wire on which he hung up washing to dry.

The family moved in during the dog days of the South African winter and came down with flu after a week. Julian and Ena effectively went on a vegan diet and each lost 5kg. They had to get used to a "smelly" long-drop toilet, the attention of rats and the absence of mod cons. "I really miss a shower," she said. "Bucket baths just don't do it for me: one kettle of water and having to wash your head upside down in a bucket is not much fun, then use the same bucket for your dishes and laundry. It takes about an hour and a half to heat it with paraffin."

But the Hewitts, who do not own a TV anyway, enjoyed extra family time, catching up on sleep and sitting around a fire each evening talking to their neighbours. Family and close friends had warned that they were being "reckless and irresponsible" by exposing their daughters to a township but the community proved caring and protective.

Ena continued: "We go for a walk every afternoon and can't go 50 metres without getting stopped, greeted, chatted to. They can't believe it when we say we're living here but they're very friendly.

"I have to wonder if it was the other way around, and in an exclusively white suburb a bunch of black people walked in, whether people would be as welcoming."

While most of the feedback on the Hewitts' blog and Facebook page was positive, there were dissenting voices who called the exercise exploitative and voyeuristic. One Twitter user wrote: "Mamelodi people must burn them in that shack."

Jessica and Julia Hewitt playing with Junior Maleka. Photograph: Jordi Matas for the Guardian

Julian, a social entrepreneur who commuted from Mamelodi to his office in Johannesburg once a week, reflected: "There is a very interesting undercurrent that we've been exposed to. There are your young, black professionals who still feel angry about that fact the status quo hasn't really changed. There is the sense that we're mocking poverty and all these things and that's OK, because they don't know us.

"But what's very interesting with those people we've found is that they're a lot more comfortable with the notion of a British tourist coming and living here for a month, because in that case it's an 'adventure' and this person's just trying to get to understand African culture better. But as white South Africans we basically are part of the problem and it opens up a whole lot of questions that might have been covered up otherwise and brings out a lot of tensions that would not be there if we are foreign tourists."

The couple were not trying to build schools or set up an NGO, he added, but simply being here was the point. "What's great is that people get what we're trying to do. The fact that we're able to interact with them as people, rather than as white people, breaks down massive boundaries reinforced in people's minds for three and a half centuries here.

"We popped into a shebeen the other day on one of our afternoon walks. A big football match was on TV and there was almost dead silence when they turned and saw two blonde girls and us and a friend. Two guys came up to us and one said, 'Wow, you make me believe God is alive today.' The other guy started quoting Nelson Mandela's Rivonia trial speech where he said: 'This is an ideal for which I am prepared to die.' He said that ideal that Mandela is prepared to die for is bringing you into a place like this."

Residents of Mamelodi appeared intrigued and impressed by the guests. They praised the family for helping their children with homework and making an effort to learn their languages. Many also expressed hope that the media coverage would move politicians to action. Nkambule's niece, Velly, 27, said: "I was very glad they came to see how we are suffering here and how much we spend on taxis and paraffin. The community is very happy and we wish they could stay forever."