Commercial rooftop greenhouses

Rooftop greenhouses (RTGs) have become an iconic symbol for integrating Controlled Environment Agriculture (CEA) in cities and have greatly inspired urban agriculture advocates, architects, and planners. Despite this positive image, few large RTGs have been built, and even fewer successful RTG farm operations exist. While built examples have shown how to master technical requirements, it is still challenging to make an economic case for commercial food production on urban rooftops and justify the high upfront investment for RTGs. This chapter identifies significant challenges and opportunities for investing in this innovative, high-tech urban farming typology based on the in-depth analysis of two exceptionally successful commercial rooftop greenhouse operations in North America – Lufa Farms in Montreal and Gotham Greens headquartered in New York City. The chapter reviews technical, practical, and legal difficulties in constructing greenhouses on roofs, establishing production systems and distribution models, as well as elaborating financial strategies for raising investment capital and pursuing business expansions. Besides considering these technical, operational, and economic factors, the study identifies typology-specific opportunities to generate additional value, marketing opportunities, environmentally sustainable building performance, and social benefits for urban communities. The chapter reflects on how RTGs can be peri-urban production facilities, contribute to new multi-purpose food centers in cities, and provide additional social services to urban dwellers. With their ability to add to multiple dimensions of sustainability, RTGs are poised to generate impactful contributions to new urban and regional food systems.