Choosing the Right Occupancy Sensor Technologies for Your Space

Rang Luo

Updated December 22, 2025 17:09

There are many types of occupancy sensors on the market, each with different capabilities, limitations, and trade-offs. The right choice depends on your use case, space type, privacy posture, and scalability requirements.

Below is a comparison of common occupancy sensing technologies and how they stack up against key performance criteria.

Sensor Type	Description	Strengths	Limitations
Passive Infrared (PIR)	Detects motion based on changes in infrared radiation from warm bodies.	Low cost Simple motion/presence detection	Cannot detect stationary individuals Cannot count number of occupants Prone to false negatives
Ultrasonic	Emits sound waves and measures changes in the echo to detect movement.	Detects small movements Works in low-visibility environments	Prone to false positives from HVAC or ambient noise No accurate headcount
Pressure-based	Uses pressure sensors embedded in furniture to detect seated presence.	High seat-level accuracy Great for workstations or call centers	Requires integration into furniture Not scalable for open/shared spaces
Wi-Fi/Bluetooth Tracking	Tracks devices connected to or visible via the building’s network.	No new hardware needed Device-based automation	Only tracks people with connected devices Room-level accuracy at best
Camera-based Vision	Uses computer vision to analyze images for people count, identity, and behavior.	High-resolution data Can detect posture, identity, and behavior	Major privacy concerns High cost and complex infrastructure May require consent
Thermal Sensors (e.g., Butlr)	Detects human body heat and movement without identifying features.	Real-time, anonymous people counting Detects stationary presence Wireless and battery-powered	No identity tracking Less detailed behavioral insight compared to video

Why Butlr Uses Thermal Sensing

Butlr’s thermal-based occupancy sensors are purpose-built to provide accurate, real-time data while preserving privacy and enabling easy deployment:

Privacy-First: No video, no audio, no PII — only body heat detection
Accurate: Detects individuals whether they’re moving or seated
Wireless: Battery-powered with 2+ year life; no rewiring or hard installs
Scalable: Simple magnetic mounting enables rapid rollout across locations
Flexible: Ideal for offices, retail, senior living, healthcare, education, and more

Thermal sensing is the most balanced approach for organizations that need reliable occupancy data without the complexity or privacy risks of camera-based or device-based systems.