Tinytag Instrumentation data loggers were used with solarimeter sensors, while Plus 2 loggers were used to measure outdoor temperatures.

Paul Baker is a consultant for Historic England, and a Senior Lecturer in Dept. Construction and Surveying at Glasgow Caledonian University. Paul has around 20 years experience of using Tinytags, including in his work at the Building Research Establishment, and recommendeds Tinytag data loggers as part of this project.

Historic England is the public body that helps people care for, enjoy and celebrate England's spectacular historic environment. Following 2015 floods in Appleby, Cumbria, Historic England has been working with Cumbria Action for Sustainability (CAfS) and partners to promote best practice in improving flood resilience and energy efficiency of buildings in the town. Part of the project included the rehabilitation of a house in the town centre as an exemplar.

The property at 33A Castle Street (listed Grade II) is a three storey wing of a late 18th century house, and was flooded in 2015.The aim of the exemplar project is to show how a house of traditional construction can be made more resilient against flooding and energy efficient using only traditional and sustainable materials. Building Conservation and Research Team (BCRT) is contributing to this project by evaluating the performance of the building before and after rehabilitation. As a first step, the thermal performance of the existing building envelope has been determined by co-heating and air pressurisation tests, as well as in situ U-value measurements of the walls, roof and ground floor. In addition, moisture profiles in the building fabric have been assessed and mapped. These tests and measurements will be repeated once the rehabilitation project has been completed and will enable the improvements to be quantified.

When the building is reoccupied, long-term monitoring of internal and external environmental parameters, internal air quality, moisture profiles and energy use will be carried out. And if the building should unfortunately be flooded again, the data acquired will enable the resilience of the rehabilitated building to be assessed.

As part of the research, Paul recommended the use of three Tinytag TGPR-1001 Re-Ed millivolt loggers, which were used with Campbell Scientific solarimeters which record sun and sky solar radiation. The latest range of Tinytag Instrumentation data loggers has now replaced the Re-ed units, providing voltage, current and count loggers for use with third party sensors in order to provide accurate and robust data loggers for specialist applications such as this.

Several robust Plus 2 TGP-4520 data loggers with thermistor probes were also used to measure outside air and building wall surface temperatures. Data is exported to Excel prior to applying a calibration factor.

This outdoor data is used in combination with indoor measurements of air and surface temperatures, heat flows through walls, and electrical power (heaters etc.) An overall heat loss and a solar gain factor were calculated, which enable an energy rating to be determined. This also gives a base line to estimate improvements in energy efficiency when improvements to the building, such as increasing insulation, are made. The individual heat flow measurements and temperature differences across the walls and surfaces are used to calculate U-values: the lower the U-value the better the insulation of the building element.

Tinytags were ideal for recording the outdoor measurements; as standalone battery powered units, they avoided the practical difficulties of hard-wiring back to an indoor logging system. The logger memory is sufficient to use a short logging interval (5 minutes or less) in order to maximise the amount of data gathered for the Appleby tests over two to four weeks.

Paul comments, "In over 20 years of successfully using Tinytags I've seen improvements in data capacity and battery life. The introduction of new sensors in the Tinytag range, such as the CO2 logger, has also increased the possibilities for relatively low cost monitoring, particularly when a small number of sensors are required in a domestic setting."

The image shows the front elevation of the building with sensors. Credit: Heritage England.