Does BIA Actually Reduce Emissions? The Contested Case
When "local" doesn't automatically mean "lower impact."
“The intuition that 'local' automatically equals 'lower impact' is frequently challenged in the literature.”
Agriculture measures performance in kilograms of CO₂ equivalent per kilogram of crop harvested. Conversely, the building sector measures performance via Energy Use Intensity (EUI), Water Use Intensity (WUI), and Greenhouse Gas Intensity (GHGI) per unit of floor area. Neither industry's foundational metric translates cleanly into the others.
The Tension
Energy and resource intensity remain primary concerns, and the intuition that "local" automatically equals "lower impact" is frequently challenged in the literature. For instance, Kulak, Graves, and Chatterton (2013) found that growing strawberries in London rooftop greenhouses produced a higher carbon footprint than importing greenhouse-grown strawberries from Spain. Similarly, Goldstein et al. (2016) demonstrated that importing tomatoes from Spain or Italy to Austria sometimes generated fewer emissions than cultivating them locally in energy-intensive controlled environments—though results varied heavily based on system design. Ultimately, conducting accurate life-cycle assessments (LCAs) for BIA remains inherently difficult due to a lack of standardized metrics and widespread inconsistencies in evaluation methods, regional contexts, and integration strategies.
The Methodology Gap
The report diagnoses a critical limitation across most of these contradictory assessments: narrow system boundaries. Conventional LCAs typically evaluate the farm in isolation, entirely excluding building-level synergies such as improved thermal insulation, waste-heat recovery, and integrated stormwater management. Because these reciprocal efficiencies are routinely omitted, the report argues that a more holistic evaluation framework—one that simultaneously measures agricultural output and building performance—is essential to accurately and fairly judge BIA's true climate impact.
In the report:
Part I, "The Role of Building-Integrated Agriculture (BIA)."