Benchmarking: kWh per Square Metre
REEB and CIBSE benchmarks for offices, the NLA vs GIA trap, and how to tell whether a building is genuinely good or just quietly typical.
10 min read · Jacob Willis, Net Zero Lead · Last reviewed July 2026
"Is this building any good?" is the first question every landlord, buyer and incoming tenant asks, and the sector answers it in kilowatt-hours per square metre per year. Benchmarking a commercial building looks like the simplest arithmetic on this platform, one division, yet it is riddled with traps: which floor area you divide by changes the answer by 20% or more, "typical" performance is a very long way from "good", and a building can beat the average while wasting a quarter of its energy. This lesson gives you the current UK reference numbers and teaches you to use them without fooling yourself.