Radiant cooling and heating has the potential for improved energy efficiency, demand response, comfort, indoor environmental quality, and architectural design. Many radiant buildings have demonstrated outstanding performance in these regards, and application of the technology in commercial buildings is expanding. However, there are no well-established best practices for design of radiant buildings and their control systems, and most professionals in the building industry are unfamiliar with radiant systems. In this study, TRC Energy Services and the UC Berkeley Center for the Built Environment interviewed eleven prominent professionals who have substantial experience with design, construction, and operation of radiant buildings in North America, having collectively designed more than 330 radiant cooled buildings. The objective of the study was to:
- Document the variety of design and control approaches currently used for radiant cooled buildings,
- Highlight themes of common practice and variations in common practice, and
- Identify areas where research could be of service to practitioner needs.
We focused specifically on design and control of high thermal mass radiant systems – referred to as Thermally Activated Building Systems (TABS). A TABS system has radiant tubing embedded in a structural slab, or in a topping slab on top of a structural slab without insulation to separate the two slabs. We also include discussion of radiant systems with topping slabs separated from structural slabs by insulation – referred to as Embedded Surface Systems (ESS).