How to spot an inefficient building even when everything seems to work

A building can seem normal while wasting energy

Occupants may be comfortable while plant equipment runs outside required hours, cooling and heating fight one another or alarms are continually overridden.

Ten useful warning signs

Look for unstable room temperatures, simultaneous heating and cooling, high night-time energy use, repeated manual overrides, recurring complaints, unexplained alarms, missing measurements, illogical sensor values, unused trend data and outdated control sequences.

How to investigate

Start with equipment schedules and measurement trends, check representative zones, examine sequences for simultaneous demands and compare actual occupancy with plant operation. Confirm sensor accuracy before changing control parameters.

Focus on user outcomes

A good diagnosis produces a clear list of observed problems, priorities and measures for verifying improvements—not just a more complex dashboard.

Practical checks for the ten warning signs

Compare representative zone temperatures with the expected schedule and setpoint. Check whether heating valves and cooling equipment are commanded simultaneously. Examine electricity demand during nights, weekends and holiday periods. Review the frequency of manual overrides and identify points that are always in a fixed state.

Analyse complaints together with measurements rather than treating them as isolated events. Frequent “too hot” and “too cold” reports can be signs of poor zone control, incorrect sensors, insufficient balancing or inappropriate schedules. The correct solution depends on technical diagnosis.

What should be visible on a useful BMS dashboard?

A practical view should show operating mode, key measured temperatures, plant status, current alarms and relevant trends. More graphics do not necessarily mean more information. If technicians cannot identify what is failing or which unit is responsible, the visualisation may need improvement.

How to prioritise corrective action

Start with safety and essential operation, then address faults causing repeated disruption. Follow with issues that appear to waste energy or compromise comfort. For each improvement, record an observation, a proposed change and a way to verify whether it helped. This approach gives managers a useful basis for making decisions.

What the building operator should inspect first

Start with the simple questions: do equipment schedules match actual occupancy; do systems hold stable temperatures; are there persistent manual overrides; and does the energy profile show unexpected overnight or weekend consumption? Then compare BMS trends with the physical system and any independent meter data.

Distinguish symptoms from causes

An unstable temperature may be caused by a sensor, hydraulic imbalance, mechanical defect or unsuitable control parameters. A high demand peak may result from several otherwise reasonable systems starting together. Good diagnostics checks evidence before changing setpoints.

Prioritising action

1. Address safety and equipment-protection risks immediately.
2. Resolve faults that repeatedly affect occupants or cause clear operational loss.
3. Correct schedules and poorly documented manual overrides.
4. Use trend data to test whether performance actually improved.

A building that is simply “still running” may still benefit from a focused operational review.