The Guide to Occupancy Sensors

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

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. The sensors are usually connected to a building’s Internet of Things (IoT) network and feed data back to building management systems and booking systems that can automate systems for lighting, HVAC and ventilation control, whilst providing data for occupancy analytics systems to understand desk usage, meeting room efficiency and space utilization.

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 movement and changes in their field of view. These sensors are simple, providing basic occupied or un-occupied data. A common example of a PIR sensor is a desk sensor that is typically placed on the underside of a desk and is used to detect and report desk occupancy.
  • 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 are advanced sensors that count people and can provide accurate data for occupancy levels and space utilization.

Advanced occupancy 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. From here, reliable data can be integrated with other systems such as lighting, HVAC or booking systems when predetermined levels are reached.

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, implement desk hoteling, improve energy efficiency, manage your meeting room sizes or enhance employee productivity? 

There are various options on the market, each offering different levels of data and integration capabilities. Accuracy, efficiency, and compliance with data protection policies through collecting anonymous data, 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. Therefore, this type of sensor is aligned for facilitating desk hoteling, however, it wouldn’t be suitable for enabling meeting room management or for understanding space usage for space planning decisions. 

Irisys True Occupancy is an occupancy ecosystem that provides essential occupancy data for everywhere that matters to you, from desks to rooms, and open areas to buildings. 

The solution gives you accurate, real-time, anonymous occupancy data enabling you to:

  • Know when spaces are occupied and how this space is being used.
  • Identify underutilized spaces, such as if you have the right size meeting rooms for the number of people that on average use them. 
  • 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 prioritized – 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 organization'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 help of this real-time data, you can action the best and most effective processes to:

  • optimize your space in order to design practical workspaces that meet the needs of your employees. 
  • improve your energy efficiency profile by reducing wastage.
  • keep on top of hygiene and maintenance throughout your estate.
  • save money on energy by controlling the lighting and temperature in vacant spaces. 
  • manage desk and meeting room usage that will enable better experience for your staff and help to improve their productivity by gaining visibility over conference room or workspace availability.

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. For example, cleaning and maintenance staff can decide on the frequency of cleaning required based on data collected by discrete washroom occupancy sensors or be alerted when a hot desk has become unoccupied to sanitize the area and equipment. 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, enabling more efficiencies and benefits to accommodate the changing needs of your building and its occupants. True Occupancy offers seamless integration through pre-built connections and standard protocols to connect reliable occupancy data with desk and meeting room booking systems, cleaning scheduling tools, building management systems and more.

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 their office layout to accommodate the new role employees will expect it to aid 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.

smart building roi

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. To book a free demo and experience the benefits of True Occupancy for yourself, get in touch with us today.

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Useful resources

From providing insights and best practices, to real world examples and use cases, our occupancy data guides will help you discover the true power of occupancy data and occupancy analytics.

eBook - Building a Business Case for Occupancy Monitoring

Building a Business Case for Occupancy Monitoring

eBook - Using Occupancy Data to Re-engage Employees With the Workplace

Using Occupancy Data to Re-engage Employees With the Workplace

eBook - Truth About Occupancy - 600x315 - White

The Truth About Workplace Occupancy