Department of Building and Environmental Technology at LTH
A Hotbox for Evaluating New Sustainable Buildning Structures
To support research into more sustainable building materials and structures, LTH needed to bring its hotbox testing facility back into operation after more than ten years. Prevas upgraded the control and measurement system, creating a flexible and reliable solution for advanced building physics research and future collaboration with industry.
Wanting to evaluate new sustainable solutions for buildnings
As a step towards finding new sustainable building materials and structures, the division of Building Physics at the Department of Building and Environmental Technology at LTH performs experiments to evaluate heat- air- and moisture transport through the building envelope.
One of the experimental setups is a hotbox where sections of exterior walls, including windows, doors etc. can be tested. Heat transfer properties and temperatures are measured to find insulation properties. Due to an outdated control system the hotbox had been out of order for over ten years. It was now time to get it up and running again. LTH saw possibilities for their own research as well as using it as an experimental laboratory for companies in the building sector.

On the picture – Jessica Dahlström from LTH and Riki Virc from Prevas.
Getting old things up and running
Due to the limited budget, much of the hardware was reused. This required some reverse engineering to find out how to control the existing heater and cooler. The measurement hardware was replaced with new CompactDAQs from NI, and all sensors were replaced.
Flexible hardware solution
The hotbox has two sides, one cold and one warm. These are separated when a test wall is placed in the hotbox. Therefore the control system hardware is split in two cabinets enabling a robust solution.
Hardware
- 53 thermocouples
- Humidity and pressure sensors
- Heater, cooler and light control
- Power measurements
- Interfacing old hardware
Software
- Control system
- Measurement sequences
- Datalogging
- GUI for operation and configuration
Industry ready for joint venture research projects
The hotbox is now up and running, waiting for new projects. LTH looks forward to starting the projects in the pipeline, which has been a bit delayed due to the Covid pandemic. The hotbox is planned to be part of the LTH Open Door External link, opens in new window., enabling industry use of research facilities.
“Prevas (former DVel) was easy to communicate with from the start. They listened and gave straightforward answers, enabling us to understand the solution already in the initial phase. During the project, Prevas had answers to any questions we had, and they delivered what was promised. We also like their close relation to research, being able to relate to our operation. We look forward to using the upgraded system”, says Lars-Erik Harderup, Senior lecturer at Division of Building Physics, LTH.