Mounting Height and Location
How high should a sensor be installed? In short: Air sensors for CO2, temperature, and humidity should be installed at a height of 1.1 to 1.7 m; motion detectors should be mounted on the ceiling at 2.5 m; people counters should be placed above the passageway at 2.2 to 2.5 m; and table sensors should be mounted on or under the tabletop. Detailed information, broken down by device and including explanations, can be found here.
At what height should a CO2 sensor be installed?
The most common questionA CO₂ sensor is installed 1.1 to 1.7 meters above the finished floor. This is the breathing zone of people who are sitting or standing, and it is precisely this air that should be measured—not the air at floor level or the air near the ceiling. Our data sheet specifies an installation height of approximately 1.75 m; where WELL certification is sought, 1.1 to 1.7 m is explicitly required. To meet both requirements, install the sensor at 1.7 m.
More important than the exact centimeter is the sensor’s location in the room. The sensor should be mounted on an interior wall, preferably opposite the door. If placed next to the door, it measures the hallway; if placed in the supply air stream, it measures the HVAC system; and if placed in the exhaust air stream, it measures a mixed value that has little to do with the room itself. As a rule of thumb, we allow for a one-meter distance from doors, windows, supply air, exhaust air, and heating and cooling surfaces.
Where certification is required, the range is specified in the guidelines: WELL v2 requires 1.1 to 1.7 m for measuring devices and displays, while RESET Air permits 0.9 to 1.8 m and additionally requires a minimum distance of 5 m from openable windows and supply air vents. Without certification, the breathing zone is considered the standard, i.e., 1.2 to 1.8 m.
The same applies to temperature and humidity: measurements are taken where people are present. A sensor on the exterior wall measures the wall temperature, and one above the radiator measures the heating. Four measurement points per floor show whether the area is being heated evenly.
Ceiling, Wall, Work Surface: The Three Levels
All devices in a tableA fully equipped floor has devices on three levels. Items that need to monitor an area are mounted on the ceiling: motion detectors, meters, and wireless receivers. Items that measure air quality or display information are mounted on the wall. Items specific to individual workstations are located at the work surface.
The following table lists the installation location, height, and reason for each device. The values are taken from the product data sheets, the model floor, and—where required by certification—from WELL.
| Device | Installation location | Height | What to Keep in Mind |
|---|---|---|---|
| EnoSense® CO2, EnoPuck® CO2 | Inner wall opposite the door | 1.1 to 1.7 m | Not next to the door, not in the supply air stream, not in the exhaust air—otherwise, the device will measure the hallway instead of the room. Our data sheet recommends approximately 1.75 m; where WELL standards apply, 1.1 to 1.7 m is required. |
| EnoSense® Temp/RH | In common areas, multiple points per floor | 1.1 to 1.7 m | At least 1 m away from exterior walls, doors, direct sunlight, supply and exhaust air, and heating and cooling surfaces. Four measurement points per floor indicate whether the area is being evenly heated or cooled. |
| EnoSense® PM VOC | Wall mounting with included bracket | Occupancy area | Particles and VOCs are measured in the breathing zone, just like CO2. Do not place the sensor in the supply air or directly next to a source such as a printer or break room. |
| EnoSense® Radon | In the room to be assessed | Living area | The measurement location should be within the room for which the certification applies—that is, in the workspace itself, not in the hallway outside it. Check the operating temperature of the installation site; the minimum temperature is +10 °C. |
| EnoSense® PIR Ceiling, PIR DOT | Ceiling, center of the room | 2.5 m | At a mounting height of 2.5 m, the detection radius is approximately 3 m. When mounted higher, the detection area increases, but sensitivity at the edges decreases. |
| EnoSense® Presence Count | Ceiling above the area to be counted | 4 m | At a mounting height of 4 m, an area of up to 7 × 3 m is detected. Mount using the holes in the base plate, with the sensors facing forward. |
| EnoSense® People Counter | Ceiling, above the passageway | 2.2 to 2.5 m, typically 2.4 m | Counts people passing through without detecting individual locations. Detection range is approximately 0.5 m in front of and 0.2 m behind the sensor. |
| EnoSense® Desk | On the tabletop | typically 0.85 m | Detection angle approximately 90 degrees; detection range about 0.5 m in front of the sensor. Oriented toward the workstation, not toward the aisle. |
| EnoSense® Desk VIB | Under the tabletop | Table height | One sensor per workstation. Installation is possible even while the office is in operation, without requiring any configuration. |
| EnoSense® LUX | For windows | Work surface | Measures natural light to ensure the lighting system only provides as much light as necessary. Avoid placing it in the shadow of a shelf or directly under a light fixture. |
| EnoSense® Window | On a window that opens | Window frame | Reports the window status to the control system so that the heating system does not work against the open window when ventilating. |
| EnoSign® Room Display | Wall-mounted, visible at the entrance | 1.1 to 1.7 m | WELL requires displays to be installed at the same height as measuring devices, with one display per 325 m². The EnoSign displays the readings from any sensor without taking measurements itself and without requiring wiring. |
| EnoDisc® Wireless Receiver | Ceiling, offset from the centerline | Ceiling height | With a planning radius of 12 m, one receiver covers approximately 450 m²; the coverage areas intentionally overlap. Connection via RJ45 or LSA, powered via PoE. |
| VL-700 BASE Gateway | Utility Room, DIN Rail | Control cabinet | One gateway per floor, with a firewall between the field network and the building network. From here, the data is sent to the building automation system. |
Where a device must not be hung
Five Mistakes That Stand Out During OperationMost complaints about “incorrect readings” are due to installation errors. Five of these errors occur time and again, and all five are cheaper to prevent during installation than to explain during the acceptance inspection.
In the supply air stream: the sensor measures the system, not the room, and the control system works against itself. Next to the door: every time the door opens, the hallway temperature is drawn in, causing the reading to fluctuate erratically. In direct sunlight or above a radiator: the temperature reading becomes inaccurate, and in combined units, the humidity level drops as well.
Behind a shelf or a plant: the air doesn’t circulate, and the reading lags behind. And if the motion detector is in the corner of the room instead of in the center: half of its detection cone points toward the wall, leaving half the room uncovered. At a mounting height of 2.5 m, a ceiling-mounted detector covers a radius of about 3 m—which only works if it’s centered.
What this means for your request for proposals
9 points- Specify the mounting height for each group of devices; do not rely on “manufacturer specifications.”
- Where WELL applies: Specify 1.1 to 1.7 m for air sensors and displays.
- Specify the installation location for each room: interior wall opposite the door, ceiling in the center of the room, above the doorway.
- Specify minimum clearances: one meter from doors, windows, supply air vents, exhaust air vents, and heating and cooling surfaces.
- For suspended ceilings, specify the lower edge as the reference point, not the exposed ceiling.
- For meters, check the clearance height: 2.2 to 2.5 m, typically 2.4 m.
- Specify fasteners and substrate for each room type.
- Determine who will install the devices: users can install table sensors themselves; ceiling-mounted devices are the responsibility of the electrical contractor.
- Require the following information for measurements and documentation: room number, device ID, and installation location.
Information current as of September 16, 2026. Regulatory information has been compiled to the best of our knowledge and does not constitute legal advice. The text of the currently applicable version is always authoritative.
- Installation heights and locations for each device are specified in the respective product data sheets (under “Installation Height”), as of September 2026.
- WELL v2, Feature A08 “Air Quality Monitoring and Awareness,” Q4 2021 version: Installation height 1.1 to 1.7 m for measuring devices and displays.
- RESET™ Air Standard for Commercial Interiors v2.0 dated January 31, 2018, Section 2.2.6: Installation height 0.9 to 1.8 m, minimum distance of 5 m from openable windows and supply air vents.
- Placement and rationale for each device from the sample floor plan on this website (121 devices, three configuration levels).
- A minimum distance of one meter from doors, windows, supply air vents, exhaust air vents, and heating surfaces is our design recommendation—not a requirement set forth by a standard.
Would you like us to run the numbers for your building?
Send us the floor plan, dimensions, and target system. You’ll receive a recommendation for the number of units, a list of part numbers, and a quote.