Green building financial return.

Green building premium (BREEAM, LEED-certified) adds 2-8% to construction cost but delivers savings in energy (20-40%), water (15-30%), and maintenance (10-20%) over the building's lifetime. ROI typically materialises in 5-10 years for new builds. Retrofit green improvements pay back faster (2-5 years) because targeted measures address biggest waste first.

500k green premium on a 10M build. Annual energy savings 80k + water 15k + maintenance 20k = 115k/year. Over 20 years: 2.3M total savings. ROI: 360%. Payback 4.3 years. Strong investment - and doesn't count increased property value (green-certified buildings sell at 5-15% premium over standard).

Green buildings also command 3-8% higher rents, 10-20% lower vacancy rates, and attract ESG-focused corporate tenants. The financial case extends beyond energy savings into asset value and tenant quality. Most institutional investors now require green certification for new developments - it's becoming table stakes, not premium.

A worked example

Try the defaults: green premium cost of 500,000, annual energy savings of 80,000, annual water savings of 15,000, annual maintenance savings of 20,000. The tool returns 360.00%. You can adjust any input and the result updates as you type — no submit button, no reload. That's the real power here: seeing how sensitive the output is to one or two assumptions.

What moves the number most

The result responds to Green Premium Cost, Annual Energy Savings, Annual Water Savings, Annual Maintenance Savings, and Analysis Period (years). Not every input has equal weight. Flip one at a time toward extreme values to feel which ones move the needle most for your situation.

The formula behind this

Total savings = (energy + water + maintenance) × years. ROI = (savings - premium) ÷ premium × 100. Everything the calculator does is shown in the formula box below, so you can check the math against your own spreadsheet if you want.

Beyond the number

Carbon, health, and local air quality don't show up on the calculator but often drive the decision. The financial figure is a lower bound on the value; the rest is whatever you'd pay for the non-financial benefits.

What this doesn't capture

Carbon reduction, health benefits, and local air quality have real value the financial figure doesn't price. The calculation gives the money side honestly; for the full picture, note the non-financial benefits alongside.