Brownfields and urban renewal

The third hallmark of the compact city is the renewal of run-down inner areas — instead of expansion, improving and densifying the existing urban fabric, with particular emphasis on bringing brownfield sites into use.

1.The self-perpetuating process of decline

The outflow of families with children from the city to the agglomeration accelerates the ageing of neighbourhoods, while the departure of wealthier groups reduces the area's financial strength, making maintenance harder as well. That is why, alongside physical renewal, social renewal is also worth supporting. At the same time, more centrally located, densely built districts hold great potential: they are closer to the urban core, their infrastructure is better developed, and they are better supplied with jobs.

2.The scales of rehabilitation

Urban rehabilitation has two main methods: "hard" rehabilitation (reconstruction), where blocks of buildings are demolished and rebuilt, and "soft" rehabilitation, where most of the building stock is retained. Beyond these, block-level and building-level renewal also exist, depending on the scale of the intervention. Projects are driven by social and/or market factors: market-logic renewal is fast, but it can easily displace long-standing residents, so social problems are not eased, only relocated in space. The compact city builds on social diversity, so rehabilitation must be shaped so that homogeneous neighbourhoods made up only of residents of similar means do not emerge.

3.Brownfields as a reserve

The concept supports brownfield investment and avoids building on forests and agricultural land. Brownfields often lie in or close to the urban core, with existing infrastructure, as remnants of former industrial or service functions — underused yet well-positioned sites. For private investors, however, they are often unattractive, because in some cases demolition and remediation fall to them as well; it may therefore be worth incentivising them, while regulating greenfield developments more strictly. Alongside classic brownfields, vacant lots can also be put to use. In their place not only buildings but even parks and other green spaces can be created, which eases the negative effects of dense development. According to one survey, more than 2,700 hectares of brownfields, vacant lots and empty buildings can be found within Budapest's administrative boundary.