homenews and insights we knew that didnt we 4 building management systems for beginners

We knew that didn’t we? #4 Building Management Systems for Beginners

By Dr Andrew Eaton
14 December 2020

Product Marketing Manager

Meet our SSE Energy Solutions experts


This is an introduction to BeMS systems for people who are new to the industry

What is a building?

The importance of buildings in our day to day life can be easily overlooked. Given that we are spending over 90% of our time indoors, we have grown accustomed to our usual surroundings without fully appreciating their impact on our wellbeing, their environmental footprint, and associated costs.

So, when is a building not (just) a building?

  • When it’s a built environment, designed for one reason and one reason only – Human Activity.
  • Thinking beyond this, it can be both a home and an office, and in 2020 that 90% has been closer to 100%.#
  • Built environments are, potentially, places of innovation, or an essential part of society such as hospitals.

These points barely scratch the surface, many more enter the equation when considering the location, occupant type and operational requirements: getting the right tool (building) for the job is important.

Simultaneously, when considering occupant orientated buildings as opposed to building orientated occupants, we must account for energy consumption, to both save money, and to ensure that our buildings are positively contributing towards the battle against climate change and achieving Net-Zero goals.


The building as a human body

Parts of the building function in a similar way to the parts and subsystems of the human body.

Figure 2 - Body-Analogy

The architectural Design represents the skin; structural design the bones, heating, ventilation and air-conditioning (HVAC) the Organs, and the BMS can be considered to be the brain and central nervous system.

Whilst the architectural design (skin) and structural design (skeleton) remain static post-completion, the HVAC (organs) and BMS (brain and central nervous system) operate continuously, where BMS directly monitors and controls HVAC systems, just like our brain controls our organs.

As we utilise our brain more and more to learn new things we consume more data. More information is absorbed and, in return, we can make ‘data-driven decisions’ whether that’s derived from study or experience. Similarly, a BMS system can become more intelligent by capturing more data and provides a better functional built environment.

Figure 3

How does a BMS work?

On a high level, it is relatively simple; all we need is four elements:


A variable that is required to be controlled such as temperature, air quality, humidity


A device that can read the value or magnitude of the parameter.


The controller has identified what is required to be done, i.e. temperature levels within a space are too high, the controller switches on the air conditioning, or to supply cooler outside air into the space, or if the temperature has dropped, the boiler is switched on to supply more heat through radiators.


A device which implements a logic or intelligence and decides if the state of the parameter is correct/incorrect, and what is required to be done.

Figure 4

Beyond Temperature Control

The common misperception that BMS only controls temperature levels within a building very often overshadows many other major factors which need to be considered when designing, commissioning and operating our buildings, we must thing beyond temperature control.

BMS functionality can be split into 4 major components:

Energy Monitoring

The most obvious one is to monitor, control and optimize energy consumption, decrease carbon footprint and energy cost.

Fault Maintenance

Recognize equipment performance discrepancies, anticipate common faults, hence avoid equipment blackouts or downtime.

Environmental Control

Controlling the temperature, air humidity, lighting, air quality, water temperatures.

Wellbeing & Comfort

Environmental control leads us to one of the most important factors to be considered within the built environment, which is wellbeing and Comfort, it’s all about the occupant, the building is designed and operated for human activity, hence the design and control of this space should be oriented around the occupant.

Figure 5

What does BMS have to do with Wellbeing?

To illustrate the significant importance of control system on our wellbeing and comfort we will use a particular example, such as air quality and its effects on the building’s occupants.

To investigate the effect of air quality, we will look at how the concentration of CO2 affects people. At the levels we are looking at, the unit of concentration used is parts per million, (ppm) i.e. the concentration of CO2 molecules per million of other air molecules.

Insufficient air quality measures such as ventilation can directly lead to an increase in CO2 concentration which has a negative impact on the behaviour of the people in the room, as shown in the figures below, Cognitive performance declines as CO2 increases.


We can conclude therefore that poor air quality can significantly impact occupant wellbeing which in return can have a negative impact on business performance and the bottom line.

In a nutshell…

Although a Building Management System may be considered the black art of the industry, it is inherently simple. The basic function of such a system is to monitor and control, while providing the best environment for the occupant, decreased energy consumption, either to reduce costs, or out of ecological concerns, and to minimise downtime due to failure of plant or other equipment, such as freezers in a supermarket.

Talk to SSE Energy Solutions about how we can help with your BMS. Call us on 0345 072 9529, or email us at info@sseenergyoptimisation.co.uk

This blog was researched and written by Ivo Krastins.