They've squatted for years, living in a 22-story building they took over in the heart of South America's biggest city.
The 350 or so families calling the Prestes Maia building home are part of Brazil's "roofless" squatter movement that's been around for years and hasn't abated despite the nation's economic boom.
Groups of the "roofless" have seized unused buildings around downtown Sao Paulo.
It is the urban reflection of Brazil's "landless" movement, which has seen hundreds of thousands of people in the countryside invade farm and ranch land in recent decades looking for room for subsistence farming.
Both movements draw in those with nothing, the legion of poor that has seemingly forever existed in Brazil, even as some 40 million Brazilians have joined the middle class since 2003.
At the Prestes Maia building, which squatters occupied in 2002, mothers wash babies in clear plastic tubs on sidewalks, blue tarps shading their backs from Brazil's tropical sun.
The more than 2,000 residents share communal bathrooms on each floor of the former office building. Steam flows from huge pots in community kitchens, where rice, beans and kale are cooked, staples of poor Brazilians' diet.
The squatters say their meager incomes, often earned in Brazil's informal economy, would never allow them to afford rent, even in slums.
Building owners are in the courts arguing the residents have illegally seized others' property. Leaders of the roofless movement say it's a societal crime to let abandoned buildings stand empty when so many homeless are living on the street.