NBS Cost Benefit Tool – prototype

This prototype tool attempts to monetise the costs and benefits of a green roof. The results show the three pillars of sustainability (environmental, social and economic). The overall impacts produced by the green roof are quantified automatically by the calculator. The results will help the user to determine the level of efficiency of the investment.

INITIAL DATA
Zone
Max. daily precipitation mm/day
Roof
Expected lifespan years
Calculate with
Initial investment €
Roof size m2
Advanced settings

Air quality

Data Average value Unit
NO2 g/m2
SO2 g/m2
PM10 g/m2
Data Extensive Intensive
Total Air Quality Improvement € €

Carbon

Data Average value Unit
CO2 emission maintenance kg/(year* m2)
CO2 emission production kg/m2
CO2 saved due to energy reduction kg/(year* m2)
CO2 stored in green roofs kg/(year* m2)

Energy

Data Average value Unit
Annual savings in energy use %

Water quantity

Data Average value Unit
Percentage of retention (extensive rooftop) %
Percentage of retention (intensive rooftop) %

Temperature reduction

Data Average value Unit
Degrees celsius outdoor °C
Degrees celsius indoor °C

Costs for extensive roofs

Data Average value Unit
Investment costs €/m2
Maintenance costs €/m2
Disposal costs €/m2

Costs for intensive roofs

Data Average value Unit
Investment costs €/m2
Maintenance costs €/m2
Disposal costs €/m2

Economic Variables

Data Average value Unit
Energy reduction €/m2
Membrane longevity (extensive) €/m2
Membrane longevity (intensive) €/m2
Acoustic insulation €/m2
Raised property value - extensive roof €/m2
Raised property value - intensive roof €/m2
Cost reduction of stormwater runoff €/m2
Improvement of air quality extensive €/m2
Improvement of air quality intensive €/m2
Provision of recreational space €/m2