Risk of thermal discomfort in renovated buildings with low-temperature heating systems

Bison code: L.28320

A lot of low-energy houses make use of low-temperature (LT) heating systems. In combination with heat pumps and solar panels, it is a widely used concept towards (nearly)-zero-energy homes. LT-heating is a proven concept, however in practice there are a lot of complaints about low-temperature heating systems such as underfloor heating systems. It is not always clear what the cause is and what effective counter measures are to avoid problems in future. It all starts with better understanding the concept of LT – heating within the building and its interaction with the users (inhabitants).

The operation of low-temperature houses is often poorly understood by inhabitants, resulting in poor thermal comfort (too cold, draught of air) and waste of energy. It is expected that a better understanding of the operation system (and improved interaction with users / communication strategy) could solve a lot of complaints. Human related aspects but also technical aspects (installation and/or building ) need to be addressed to solve the problem. Improving communication between installer and inhabitants seems an important aspect.

How to tackle misleading expectations of habitants about the floor-response time, setting of inappropriate heating setpoints, application of insulating floorcovering carpets, bad layout of piping in the floor, draft of cold air from the façade, asymmetric radiation by large windows, etc?

Generally spoken, inhabitants need to be better informed about the functioning of low-temperature heating systems (How does it work?, What (not) to expect?, system setup, etc). Architects, installers and builders must be more aware of risks concerning LT- heating systems in houses and how to avoid them. By determining the potential risk factors and estimating the potential risk for a specific house, a list of measures can be derived to prevent problems and to reduce complaints.

You will start with an inventory of experiences with LT-heating in practice. Discover the type of problems with the target audiences. What are the main causes of thermal discomfort and energy waste related to LT-heating in relation to building/installation aspects. What means are there to solve the problems, during the design phase of the house and in use?

You will develop a questionnaire, a risk map for houses and potential solutions, and communication strategy for new built and renovated houses, to be used by installers, architects and builders. You will also provide advice on: “How to manage potential risks towards thermal discomfort and energy waste with LT-heating systems?” and “How to communicate the performance limits to the inhabitants?

Cluster: Experience Buildings & Environment 1