Rooftop Farming Yield Calculator

The calculator estimates annual yield by multiplying usable growing area, base crop yield per square meter per cycle, cycles per year, and an adjustment factor that reflects real rooftop conditions.

• Usable Area (m²) = Roof Area × (Usable % ÷ 100)
• Effective Sun Hours = Sun Hours × (1 − Shade % ÷ 100)
• Total Adjustment Factor = System × Density × Survival × Pest × Weather × Light × Irrigation × Nutrient × Skill × CO₂
• Annual Yield (kg) = Usable Area × Base Yield × Cycles/Year × Total Adjustment Factor
• Annual Revenue = Annual Yield × Market Price
• Annual Operating Cost = Annual Yield × Operating Cost per kg
• Annual Amortized Capex = Capex Total ÷ Amortization Years
• Estimated Profit = Revenue − Operating Cost − Amortized Capex

1. Measure total roof area and estimate the usable percentage.
2. Select your system type and crop, then set annual cycles.
3. If you have trial data, override the base yield value.
4. Enter realistic loss and performance scores for your site.
5. Add pricing and cost assumptions to estimate profitability.
6. Click Calculate Yield to view results above the form.
7. Download CSV or PDF reports for sharing and records.

Structural load checks

Rooftop farming starts with engineering reality. Convert roof area into usable growing area, then confirm allowable dead load and live load for saturated media, stored water, people, and equipment. Plan clear service corridors, parapet setbacks, and safe access routes. Early yield estimates help justify reinforcement, drainage upgrades, and waterproofing protection details. Include wind exposure checks, edge protection, and fire access coordination so the farm remains compliant throughout construction and operations.

System design choices

System selection changes productivity and construction scope. Soil beds are simple but respond strongly to weather and inconsistent irrigation. Raised beds improve drainage, rooting depth control, and workflow. Hydroponic and aquaponic systems increase output when plumbing, filtration, and monitoring are reliable. Greenhouse enclosures stabilize temperature, reduce wind damage, and extend cropping seasons.

Crop cycle planning

Annual production is driven by harvest cycles, not one planting. Fast crops can deliver many cycles, while fruiting crops require longer occupancy. Set cycles per year using local climate and your planned protection level. Combine cycles with survival rate, pest loss, and weather loss to reflect real operating conditions and avoid optimistic financial projections.

Site performance drivers

The adjustment factor summarizes key drivers that shift yield. Effective sun hours account for shading from adjacent towers, mechanical screens, and parapets. Irrigation efficiency influences moisture stability and nutrient uptake. Nutrient management and operations skill scores represent monitoring discipline, timely interventions, and harvest handling. Optional CO₂ enrichment can add a modest uplift in controlled environments.

Water and economics

Water, energy, and unit costs determine viability. The calculator estimates annual water volume from daily demand and usable area, and annual energy use from cycle-based allowances. Revenue follows yield and market price, while operating cost per kilogram captures labor, inputs, and packaging. Amortized setup cost spreads capital investment across years for comparable annual profitability. Run scenarios to test sensitivity before finalizing design. If profit is negative, adjust cycles, reduce losses, negotiate pricing, or phase capex to match verified demand and conservative maintenance staffing assumptions.