Every month I’m downloading onto my computer readings from half a dozen data loggers that I have distributed around the property – five inside and one outside. The idea is to identify any locations where the fabric might be at risk of deterioration due to condensation, as well as to obtain a clearer picture of how the building is performing in order to help guide me with the changes I make to the levels of thermal insulation and ventilation as part of my renovation project.
I purchased the loggers online from http://www.tomsgadgets.com (Lascar EL-USB-2). They record air temperature, humidity and dew point (the temperature at which water vapour in the atmosphere begins to condense). The devices, which are battery-operated, are currently set to sample at hourly intervals. The data stored is downloaded by plugging the logger straight into a computer’s USB port and running the purpose-designed software that comes with it. The data can then be graphed, printed or exported to other applications.