Specifying a BMS against real operating conditions
By SCI Editorial ·
Most BMS specifications are written against design-stage assumptions: a standard occupancy curve, a single tariff, a stable tenant mix, a designed-for-spec equipment selection. None of those survive contact with year-one operation.
What to spec against actual operating conditions
- Schedules: spec for the operator's ability to override, not for the design assumption.
- Setpoints: spec the boundaries the operator can work within, not the single optimal value.
- Reporting: spec for the questions the estates team asks at week 26, not week 1.
- Alarms: spec the rationalisation discipline, not the alarm list.
- Change control: spec the workflow that lets graphics, setpoints and schedules be updated safely after handover.
Each of these costs almost nothing at design stage and is expensive to retrofit. The discipline is asking the operations question at procurement, not at handover.