The Guide To Occupancy Sensors

What are occupancy sensors, how do they work and how can you make your building smart?

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What are occupancy sensors?

person walking into office



An occupancy sensor is an electronic device that detects the presence of a person. There are various occupancy sensing technologies, but the most common are infrared, microwave, ultrasonic, and video image processing. Occupancy sensors are usually connected to a building’s Internet of Things (IoT) network and feed data back to alarms or building automation systems for lighting control, ventilation, and zone access.

How do occupancy sensors work?

Occupancy sensors work by detecting motion and changes in their environment; each sensing technology does this in a different way, for example:

  • Basic PIR (passive infrared) sensors detect changes in temperature (body heat).
  • Ultrasonic sensors emit high-frequency sound waves, outside of human hearing range, and use the doppler effect of returning sounds waves to detect people.
  • Time of flight infrared sensors use a similar principle as ultrasonic sensors; however, instead of sound, they use infrared light. By emitting invisible infrared light, AI onboard these sensors learns their surroundings and detect changes when people pass by.

These sensors are typically installed in strategic locations to pick up motion in high-traffic or isolated areas. Designed to be discreet, they are typically ceiling-mounted devices that detect individuals and groups entering or exiting a zone – building, floor, room, etc. 

The data collected is then transmitted to a cloud-based platform where AI algorithms can calculate real-time occupancy levels and space utilisation, firing off pre-determined commands to the connected automated devices such as lighting or HVAC systems.

person working


What are the best occupancy sensors?



The smart building technology you invest in will largely depend on the needs of your organisation. Are you looking to optimise your space utilisation, improve energy efficiency, or enhance employee productivity? 

There are various occupancy sensors on the market, each offering different levels of data and integration capabilities. Accuracy, efficiency, and compliance with data protection policies should be amongst your top priorities when selecting an occupancy sensor. A PIR sensor, for example, will only tell you whether a zone is occupied or not – not the number of individuals in it. Details like this are significant if you're trying to understand usage and come up with better solutions for floor plans and facilities. The True Occupancy sensors, on the other hand, will give you accurate real-time occupancy data. Access to precise and comprehensive occupancy information enables you to:

  • Know when the occupancy limit is reached for a room.
  • Alert cleaning teams to attend to washrooms once a certain number of visitors have made use of the facilities. 
  • Identify high footfall locations and ensure that these zones are well managed from a hygiene and utility perspective. 

How can a bathroom occupancy sensor improve the hygiene of your building?

Office hygiene is a considerable challenge for businesses around the world –  in the UK businesses lose £13.7 billion annually due to the problem. 

Bathroom occupancy sensors give your facilities management team anonymous insight into washroom usage, allowing for cleaning staff to be deployed when a certain quota of visitors is reached. By receiving automatic notifications, your ablution facilities will be regularly attended to, and users can rest assured that their health and hygiene is prioritised something that will be of high concern with the return to work post-COVID.    

Effective management of washrooms reduces maintenance costs, ensuring that these facilities are seen to when necessary and before issues become hazardous.  

Businesses and managers of public environments are increasingly conscious of the detrimental effects that poor washroom facilities could have on an organisation's reputation. Prospective employees or patrons will feel disinclined to accept a role or support a business that does not place importance on the hygiene and wellbeing of the occupants who frequent its premises. 


commercial bathroom


Benefits of occupancy IoT sensors




More and more businesses and organisations are growing increasingly conscious of the inefficiencies that their buildings may exhibit. With mounting concerns about energy consumption, hygiene, and occupants' user experience, incorporating occupancy IoT sensors into your facilities management systems can significantly improve the performance and utility of your buildings.

With the real-time data collected from your occupancy sensor, you can:


  • Design practical workspaces that meet the needs of your employees. 
  • Save money on energy by controlling the lighting and temperature in vacant spaces. 
  • Improve your energy efficiency profile by reducing wastage. 
  • Provide immediate visibility over conference room or workspace availability.
  • Allocate infrastructural resources to the parts of your building that need it the most. 
  • Keep on top of hygiene and maintenance throughout your estate.
  • Deliver excellent user experience while still maintaining the privacy of your occupants.

Using social distancing sensors to comply with COVID-19 regulations

The application of occupancy sensors in the workplace has expanded to helping businesses comply with social distancing regulations implemented due to COVID-19. The sensors enable your business to easily monitor the number of employees in the building or within individual floors or spaces, such as washrooms, canteens, meeting rooms, reception and collaboration areas. This is a crucial step towards getting employees back in the office as it enhances safety measures by ensuring that capacity limits are not exceeded. As a result, your employees can see that efforts have been made to prioritise their health and wellbeing, helping to reduce any concerns or anxieties about returning.

Social Distancing sensors


The connection between occupancy sensors, occupancy analytics and smart buildings

occupancy sensors in office

Smart building technology is driven by the demand for more sustainable building management practices, energy efficiency goals, and the necessity to create dynamic, responsive, and optimised environments for occupants.

The electronic hardware you choose to install throughout your smart building needs to effectively integrate and feedback into your existing platforms so that you can experience the long term benefits of making such an investment. True Occupancy sensors collect and store data in a cloud platform that allows different stakeholders to view and analyse this information remotely or whilst on-site. 

As the necessity for automation accelerates in the smart building realm, you'll want technologies that can scale with your growing requirements. True Occupancy offers seamless integration through APIs, enabling more efficiencies and benefits to accommodate the changing needs of your building and its occupants. 


How can you use occupancy detection sensor data to prove ROI?

The real value in installing occupancy detection sensors is the data you can collect and analyse to help you make more practical and ROI based decisions. 

COVID-19 has caused a shift in attitude regarding remote working, making it necessary for traditional office environments to transform. Businesses will have to review the widely accepted open plan approach that many offices have been structured around as well as optimise or reduce space that is no longer required as a result of fewer employee numbers using the building.

Your decisions to renovate, improve, or enhance a space need to be fact-based. With the implementation of occupancy sensor technology, you can have access to data that:

  • Helps you understand exactly how occupants use your building.
  • Verifies underutilised spaces.
  • Captures the flow of occupants throughout a space. 

With the help of this data, you can action the best and most effective processes to manage usage, hygiene, maintenance, and energy consumption.

It's likely that the influence of COVID-19 on how we utilise commercial space will be long-lasting. Occupancy sensor data can help you to create optimal working conditions for your employees through understanding how they are actually interacting with the space you provide them. This will help your business to remain flexible and to easily adapt when new challenges arise.

For more information on how we've helped our partners get results from their occupancy sensors, view our case studies and resources here.

True Occupancy Reporting

How our occupancy sensors work

True Occupancy offers one of the most comprehensive solutions on the market. Our occupancy sensors connect to an intuitive dashboard that gives your property and facilities management teams immediate insight into a building's real-time utilisation. From there, decision-makers can analyse the data, track performance against KPIs, and make adjustments at the most effective times. 

Our devices are non-intrusive, protect the privacy of occupants, and provide a cost-effective means of scaling your monitoring strategy as and when you need to. 

True Occupancy sensors can be found globally in office spaces, restaurants, washrooms, meeting rooms, universities and a host of other on-site facilities. We are trusted by many well-known organisations to assist with space planning, cost-saving initiatives, occupant wellbeing and employee productivity strategies.

Discover how we can help you implement occupancy sensors into your workplace