The use of accurate and fine-grained occupancy information in building operation can, in addition to providing visualization of space use, provide worthwhile energy savings when the operation of lighting, heating, ventilation and air-conditioning systems are tailored to actual building occupancy information. Although there are ample off-the-shelf heterogeneous occupancy sensors available for use in practice, the information provided is often coarse-grained and inaccurate. As a result, multiple sensors, which cost more to install and maintain are often used in building operation for occupancy driven control of lighting, heating, ventilation and air-conditioning systems (L-HVAC). This article presents results from the experimental evaluation of chair sensors using sensing techniques based on strain, vibration and a mechanical-switch for occupancy detection in an office space. In addition, results from the application of one of the chair sensors in an open-plan office space as a heterogeneous occupancy detection system for occupancy-driven control of the lighting system in the space is as well provided. (C) 2015 Elsevier B.V. All rights reserved.