In Roeselare, Belgium, a giant glass greenhouse rises above a wholesale market for fruit and vegetables. From the road, it looks like an industrial building has sprouted an entirely new roof. Inside, researchers grow crops, test methods and welcome visitors interested in how cities might produce more food.
The building is Agrotopia, designed by van Bergen Kolpa Architects and META architectuurbureau. Completed in 2021, it covers around 9,500 square metres above the existing REO Veiling market complex.
It is a useful example of a question that keeps coming back in contemporary urban design: what else could happen on top of our buildings?
Most roofs are occupied by equipment, solar panels, storage or little more than waterproofing. Rooftop farms introduce a different use, turning elevated space into an area for growing food.
They can take many forms. A school might have a modest vegetable garden. A housing development could include shared planting beds. Larger projects may use greenhouses with controlled growing systems.
The scale determines the architectural challenge. Planting a few herbs in containers is very different from building a working greenhouse with water storage, staff access and a heavy growing system.
Agrotopia is not a decorative garden. It is a research and education facility on the roof of an existing building tied to the region’s food supply.
Its tall glass enclosure makes food production visible to the city. A large staircase connects visitors to the elevated growing areas, while teaching and research spaces give the building a public purpose.
The project uses captured rainwater for irrigation and explores ways to exchange heat with the building below. Its relationship with the market is not just visual. Both facilities belong to a larger network of food production and distribution.
That link is what separates Agrotopia from an isolated rooftop attraction.
It is tempting to imagine that any flat roof could become a farm. In reality, crops, planting containers, stored water and wet soil can place substantial loads on a structure.
Buildings need to be assessed before growing areas are added. Waterproofing, drainage and safe access are essential, and plant growth can be difficult in exposed wind or strong summer sun.
A greenhouse brings another set of requirements: cooling, ventilation, water management and the need to provide suitable conditions for crops throughout the year.
For an existing building, those demands can be expensive. Rooftop agriculture succeeds when it is designed as part of the structure and operations, not added as an afterthought.
What makes rooftop farms architecturally appealing is their ability to change how people use a building.
A roof might become a place for school visits, cooking workshops or shared gardening. In residential developments, growing spaces can give neighbours an activity that goes beyond sitting together on a terrace.
But the social benefits depend on access. A rooftop farm hidden behind a locked door contributes very differently to city life from one designed for education and community use.
Agrotopia takes the public role seriously by making agricultural research visible and accessible.
Rooftop farms will not replace the land needed to feed entire cities. They can be costly to build, and some crops are much better suited to controlled environments than others.
Their contribution is more targeted. They can make use of suitable existing space, connect people with food production and create new relationships between buildings and local infrastructure.
At Agrotopia, the most remarkable part is not simply that vegetables grow above a market. It is that the architecture makes that process a visible, central feature of the city rather than something hidden at its edges.
Photo by Filip Dujardin