Monitoring indoor thermal performance in a National School Property Portfolio

ABSTRACT The New Zealand Ministry of Education has a single electronic monitoring device (sensor) that simultaneously measures five environmental elements (light, temperature, relative humidity, noise, and carbon dioxide levels) in some schools. The aim is to develop an indoor environment monitoring protocol to inform proactive assets management of school buildings. This study used observations and actual measurements of these environmental variables in three typical classrooms in three schools, to assess whether the use of a one-point sensor in one location could predict the thermal condition across a classroom. The results revealed that a single sensor located at a height of 1.5 m on an unglazed vertical wall with a low thermal mass, and away from direct sunlight, heating and cooling systems, and drafts from open windows can be used to identify good and poor thermal conditions in classrooms. A one-point sensor provides a general indication of the thermal performance of a room, but not the thermal variations across the room. This study provides a systematic method for using a single sensor to monitor thermal performance in a large school property portfolio for early discrimination from hundreds or more classrooms to direct thermal intervention programmes for large groups of school buildings.