Open Source Building Science Sensors (OSBSS): A low-cost Arduino-based platform for long-term indoor environmental data collection

Accurate characterization of parameters that influence indoor environments is often limited to the use of proprietary hardware and software, which can adversely affect costs, flexibility, and data integration. Here we describe the Open Source Building Science Sensors (OSBSS) project, which we created to design and develop a suite of inexpensive, open source devices based on the Arduino platform for measuring and recording long-term indoor environmental and building operational data. The goal of OSBSS is to allow for more flexibility in synchronizing a large number of measurements with high spatial and temporal resolution in a cost effective manner for use in research projects and, eventually, in building automation and control. Detailed tutorials with instructions for constructing the data loggers using off-the-shelf electronic components are made available freely online. The project currently includes a variety of sensors and data loggers designed to measure a number of important parameters in buildings, including air and surface temperatures, air relative humidity, human occupancy, light intensity, CO2 concentrations, and a generic voltage data logger that can log data from a variety of other sensors such as differential pressure sensors. We also describe results from co-location tests with each data logger installed for one week in an educational building alongside their commercial counterparts, which demonstrate excellent performance at substantially lower costs. •OSBSS is an inexpensive open-source platform for logging building environmental data.•Sensors include air temperature, relative humidity, occupancy, light, CO2, and more.•Tests alongside commercial counterparts demonstrate excellent performance.•Tutorials for constructing the data loggers are online at www.osbss.com