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Out-of-Hours Waste & BMS Quick Wins

A building is empty two-thirds of its hours: reading the overnight base load, and the scheduling, setpoint and dead-band fixes that cost nothing.

10 min read ยท Jacob Willis, Net Zero Lead ยท Last reviewed July 2026


The cheapest energy project in commercial property is almost always the same one: make the building's operating hours match the occupants' hours. An office is empty around 103 of the week's 168 hours, and the load-profile lesson showed that what a building draws at 3 a.m. is the fastest test of how well it is run. This lesson turns that observation into method: how to read out-of-hours waste from half-hourly data, the BMS fixes that eliminate it for little or nothing, and why these savings quietly evaporate unless someone owns them.