Question 1

How is the EUI (kWh/m²·yr) calculated?

Accepted Answer

EUI = (annual electricity kWh + annual gas kWh) ÷ floor area in m². For example, with 320,000 kWh of electricity, 180,000 kWh of gas and 2,000 m² of floor area, EUI = 500,000 ÷ 2,000 = 250 kWh/m²·yr.

Question 2

What rating bands are used for each building type?

Accepted Answer

Typical EUI bands are office 80–200, retail 100–300, warehouse 40–120, hotel 150–400 and school 80–220 kWh/m²·yr. Each band is divided into thirds: the lower third is rated Good, the middle third Typical, and the upper third (or anything above the band) Poor.

Question 3

How are retrofit savings estimated?

Accepted Answer

Savings are calculated as a percentage of the current annual energy cost: a 15% moderate retrofit saves 0.15 × annual cost (e.g. 0.15 × €95,000 = €14,250/yr) and a 30% deep retrofit saves 0.30 × annual cost (e.g. 0.30 × €95,000 = €28,500/yr).

Category	Share	kWh	€ / yr
HVAC	45%	—	—
Lighting	20%	—	—
Equipment	20%	—	—
Other	15%	—	—

Scenario	Savings	€ / yr
Moderate retrofit (15%)	—	—
Deep retrofit (30%)	—	—

Commercial Building Energy Audit Calculator

Building inputs

Audit results

Estimated end-use breakdown

Retrofit scenarios

Why this matters