Air infiltration in buildings has multiple consequences on energy use and indoor environmental quality. Therefore, in the last 10 years many countries have introduced requirements for building airtightness in their EP-regulation. Those requirements often prescribe that a test is performed by a qualified tester and that every test performed is recorded in a database.  Hundreds of thousands of data are now available in Europe.

Various studies have shown that ductwork leakage has a major impact on energy use (i.e. increased fan energy use, heating & cooling losses etc.). However, in most European countries, it is not common to perform ductwork airtightness tests, which is probably due to the lack of awareness on the consequences of ductwork leakage. As follows, ductwork airtightness is not properly taken into account in most Energy Performance Regulations and Calculations.

Over the past few years, there has been an increasing number of airtightness tests performed in Europe either for specific high performance buildings programmes or for a wide range of buildings in regulatory contexts. This has led to the development of competent tester schemes to contain potential legal and competition issues.

The objective of this webinar was to give information on the status and trends in airtightness testing in Germany, the Czech Republic and France including the details and feedback on competent tester schemes.

Setting sustainable urban development goals and developing energy efficient solutions for buildings are crucial elements of climate action. Urban living is introducing new challenges both for architectural design and technical solutions. Ventilation systems have an important impact both on energy use as well as indoor climate and health in buildings. So, how can we develop good home ventilation solutions fit for urban living?

Progressing the scientific basis of indoor environmental quality is essential to understand which aspects can be better optimised to substantially reduce energy use in buildings. In recent years, IEA Energy in Buildings and Communities (EBC) international research projects have been investigating for this purpose both indoor air quality and thermal comfort. The embodied impacts of buildings and their services systems are also a focus of EBC's research.

Setting sustainable urban development goals and developing energy efficient solutions for buildings are crucial elements of climate action. Urban living is introducing new challenges both for architectural design and technical solutions. Ventilation systems have an important impact both on energy use as well as indoor climate and health in buildings. So, how can we develop good home ventilation solutions fit for urban living?

Setting sustainable urban development goals and developing energy efficient solutions for buildings are crucial elements of climate action. Urban living is introducing new challenges both for architectural design and technical solutions. Ventilation systems have an important impact both on energy use as well as indoor climate and health in buildings. So, how can we develop good home ventilation solutions fit for urban living?

Work performed so far in the field of ductwork airtightness has shown that it may lead to important energy losses and increased fan energy use. Nevertheless, a recent survey has shown that ductwork airtightness does not seem to be taken into account (neither in regulation nor in energy performance programmes) in most European countries. Progress is therefore needed to better understand the impact of ductwork airtightness on energy use (fan, cooling and heating) and indoor air quality.

The objective of this webinar was:

Ventilative cooling is the use of natural or mechanical ventilation strategies to cool indoor spaces. It can significantly reduce the cooling energy demand in summer or mid-season conditions. Therefore, ventilative cooling is increasingly common in NZEBs.

This BUILD UP Web Seminar addressed the following: