Building Management Systems: Why Most of Them Stop Being Used

A BMS is installed, commissioned and then quietly reduced to a screen nobody reads. The reasons are consistent and largely avoidable.

A building management system should give an owner control of schedules, visibility of faults and evidence of how plant is behaving. In practice many become an expensive alarm screen with hundreds of unacknowledged notifications, a control strategy that was bypassed years ago, and a licence that only one contractor can renew. The pattern repeats because the same mistakes are made at procurement.

Why these keep happening

The system is bought as a package of hardware and points rather than as a set of outcomes the owner wants. Nobody specifies what it must control, what it must report, who will use it or what happens when the installing contractor leaves. The result is a technically complete installation that fails operationally, because the operational requirements were never written down.

1. Buying a points list instead of an outcome

Tenders are frequently written as a count of inputs and outputs. That specifies the wiring but not the behaviour, so the control logic is written by the contractor to whatever interpretation is cheapest. The owner then receives a system that monitors everything and optimises nothing, because no document ever stated what good operation looks like.

• Avoid it by: Specify the sequence of operation for each system in plain language before tendering.
• Proof it is closed: A written sequence of operation, approved by the owner, forming part of the contract documents.

What it costs you: A monitoring system paid for at the price of a control system.

2. Accepting handover without the control strategy documented

When the logic lives only inside the controller, nobody can audit whether it is doing what was intended, and a change years later becomes guesswork. Owners regularly discover during an energy review that plant is running on temporary logic installed to resolve a commissioning problem and never revised.

• Avoid it by: Require the as built sequence, the graphics and the schedules as documents at handover.
• Proof it is closed: A document set that lets an independent engineer explain the behaviour without logging in.

What it costs you: Permanent temporary settings, usually in the direction of running more equipment than needed.

3. Leaving licences and programming access with the contractor

Many platforms require engineering tools and licences that the installing contractor holds. If those are not transferred, every schedule change, sensor replacement or alarm adjustment becomes a chargeable visit, and competitive tendering for maintenance becomes impossible. This single omission shapes the cost of the system for its entire life.

• Avoid it by: Make transfer of licences, tools and administrator credentials a condition of final payment.
• Proof it is closed: Licences registered in the owner name, verified by logging in without contractor assistance.

What it costs you: A permanent single supplier relationship with no price pressure.

4. Allowing alarms to become noise

Systems are commissioned with every conceivable alarm enabled and no priority structure. Operators face hundreds of notifications daily, most of them meaningless, so they stop reading them. Genuine faults then sit unnoticed among the noise. An alarm nobody acts on is worse than no alarm, because it creates a false sense of supervision.

• Avoid it by: Rationalise alarms into priorities with a defined response for each high priority item.
• Proof it is closed: An alarm report showing a manageable daily volume and a response record for critical alarms.

What it costs you: Real plant failures running undetected for weeks inside a system designed to detect them.

5. Nobody holding the operator role

The system needs a person who reviews trends, adjusts schedules when occupancy changes and investigates anomalies. Where facilities management is a reactive call out contract, nobody owns this role. The system is then used only to silence complaints, usually by overriding whatever control was limiting the plant.

• Avoid it by: Name the operator in the maintenance contract with specific monthly duties and reporting.
• Proof it is closed: A monthly report listing schedule changes, overrides applied and overrides removed.

What it costs you: Every complaint resolved by running more equipment, permanently.

6. Letting overrides become permanent

An override is a legitimate tool for a temporary problem. It becomes a liability when it is applied during a complaint and never reversed. Years later the plant runs continuously because of an override whose original reason nobody remembers, and the control strategy exists only on paper.

• Avoid it by: Require every override to carry a reason, an owner and an expiry date in the system.
• Proof it is closed: A monthly override report with each entry either justified again or cleared.

What it costs you: Continuous operation of plant that the design intended to run on a schedule.

A short check before you sign

• Ask for the as built sequence of operation and check whether the plant behaviour matches it.
• List every active override with its date, reason and the person who applied it.
• Count the alarms generated in the last seven days and how many received a recorded response.
• Confirm whether you can log in with administrator rights without contacting the installer.
• Check the last calibration date for the sensors that drive the main control decisions.

If it has already happened

Recovering a neglected system starts with documentation, not with hardware. Commission an independent engineer to record what the system currently does, compare it with what the design intended, and produce a corrected sequence. Then clear the overrides one by one, with a named person watching for consequences. Rationalise the alarms before anyone is asked to monitor them. Secure the licences and credentials even if that requires a commercial negotiation, since without them every subsequent improvement is priced by a single supplier who knows it. Where a maintenance contract stands in the way, have a licensed adviser review your termination and transfer rights before you act.

Domira works on buildings that already exist: surveying what is installed, specifying the systems that have to be replaced, and running maintenance and refurbishment work around the people using the property. Tell Domira which asset you are responsible for and we will say what we would inspect first.