What is a BMS?

If you’re working in a facilities department for a large office or building, you may well have been asked to look into a BMS, or Building Management System.  So, for the uninitiated, we’re going to look at what exactly is BMS and what can it do.  Our aim is that, by the end of the article you should be in a position to say whether a BMS is the way to go for you and your organization.

We’ll start with the very basics, follow that up with a very brief FAQ section, and wrap it all up with a short conclusion.

What is a BMS?

A building management system (BMS), also known as a building automation system (BAS), is a computer-based control system installed in buildings to both monitor the building’s mechanical and electrical equipment, and to control it accordingly.

The different systems it can work on are many and varied.  Here follows a list (not an exhaustive one) of such systems:

  • Electrical power
  • Lighting control
  • Plumbing and heating
  • Ventilation and air conditioning
  • CCTV and security systems
  • Lifts and elevators etc
  • Fire alarm systems

Basically it can be used to control both a building’s internal environment and also the building’s security.  And when used to best effect, a BMS can improve energy efficiency, looking after operational costs (energy bills) and the environment, and it can be good for risk management to boot.

Now let’s look at exactly what kinds of things it can do.

What can it do?

The best way to explain what a BMS can do and what it’s capable of doing is by going through some concrete real world, everyday examples.  So here are a few for you in no particular order.

  • It can switch off the heating in a room if the door is left open
  • It can switch off lights and air con in a room when it is empty
  • It can turn on a light in a room where a motion detector has picked up a signal
  • It can turn on a CCTV camera where a motion detector has picked up a signal
  • It can let you select a room temperature for a meeting
  • It can let you reserve a car parking space
  • It can create a visitors badge that only allows access to preselected rooms

This is by no means an entirely exhaustive list, but more of a snapshot.  However it is important to note at this point that not all Building Management Systems will necessarily do all of the things on the list.

This is why we recommend that you draw up a list of what you want your BMS to do for you, before you approach a provider for a quote.

But that’s not all.  Where a well configured BMS really comes into its own is in risk management.  For example when a fire alarm is activated it can be used to close dampers in the ventilation system to stop smoke spreading, send all the lifts to the ground floor and force them to remain there to prevent people from using them, shut down air handlers, start smoke evacuation fans, and so on.

With regards to building security, the BMS can record which employees have and have not left the facility, which can become very useful in an emergency situation.  It’s also great for post event security evaluation by way of producing an event log and incident reports.

What are the benefits of a BMS?

Of course the primary benefit of a well configured BMS is that it allows facilities managers to generate cost savings and reduce the building’s environmental impact.  A 100,000 square foot building can potentially gain a considerable 15 percent in annual energy savings.  And in terms of financial costs you could be looking into the thousands of dollars.

Moreover troubleshooting is far easier with a BMS, because all the data gathered on the building is available in one place on the Human-Machine Interface.

And that’s not to mention the security benefits we’ve made reference to here and there.

Now that we’ve covered the main points, let’s take a look at some of your most frequently asked questions on the subject.

Answers to your most frequently asked questions

Is it the same as SCADA?

For those of you who don’t already know, SCADA, which stands for Supervisory Control and Data Acquisition, is also a centralized system that monitors and controls the entire building.  It works via a supervisory system gathering data, and is controlled via a Human-Machine Interface for monitoring and control.  So you can certainly see why someone might ask the question!

There are however, significant differences between these two types of systems, and there are advantages and disadvantages to each.

First off while BMS systems are focused on buildings, SCADA covers whole areas, including additional elements such as water treatment and distribution, wastewater collection, oil and gas pipelines, and so on.

A SCADA system also works faster, is made of more robust material, and lasts up to twice as long as a BMS.

However there are some advantages that a BMS has over a SCADA system.  It has a noticeably lower initial cost and lower operating costs.

Does it have to be bespoke?

Building Management Systems are generally bespoke systems, because even if two buildings are identical, the needs of those in the building will not necessarily be identical.  Building Management Systems are specifically tailored to the particular needs of the customer.  There is no “off the shelf” option, and as such in order to get an idea of the potential overall cost, it’s best to approach a BMS provider for a quote.


A Building Management System makes for a very useful and easy to use means of controlling the internal environment of a building, along with it’s security and it’s operational costs.  You can future proof your facilities management operations and make optimising for energy efficiency a breeze.  Something your company’s Corporate Responsibility will certainly be interested to hear about.


What is a BMS?


Last updated:

Posted in:

Got Something To Say?

Your email address will not be published. Required fields are marked *