Major discrepancies are found between countries regarding both the building and ductwork airtightness trends, primarily due to varying national policies, construction practices, and climates. In some countries, minimum airtightness requirements for buildings are included in regulations, such as in U.S. states that have adopted the IECC energy code, which mandates testing to justify airtightness in residential buildings. In Estonia and Germany, achieving high airtightness in the building envelope is encouraged by disadvantageous default values for Energy Performance calculations.

The inspection of ventilation systems in non-residential buildings is a growing priority across Europe, driven by the need for better energy efficiency and indoor air quality. Inspection protocols can be challenging to develop as, unlike for residential buildings, a wide range of building types and use has to be covered. Moreover, inspection protocols vary significantly between countries due to different national policies and building practices.

Climate change is leading to increasingly frequent and severe heatwaves, which elevate the risk of human thermal stress in indoor environments. These conditions can make buildings uninhabitable during extreme events and long after they have passed. Therefore, it is crucial to design future-proof buildings and systems that can withstand such shocks and mitigate their impact on human well-being. This performance is known as thermal resilience to overheating.

Personal Environmental Control System (PECS) with the functions of heating, cooling, ventilation, lighting and acoustic has advantages of controlling the localized environment at occupant’s workstation by their preference instead of conditioning an entire room. This improves personal comfort, health and energy efficiency of the entire heating, ventilation, and air-conditioning (HVAC) system substantially. Personalized ventilation will also provide improved protection against cross contaminations, which are critical in open plan offices and workplaces with close distance.

In recent years ventilation system design has seen a shift from design methods based on prescribed flow rates and standard lay outs, towards performance-based approaches which offer opportunities for smart ventilation concepts by considering what ventilation should achieve in terms of indoor air quality and energy efficiency.

There have worldwide been many activities during and after the COVID-19 pandemic to develop guidelines, standards, or new regulations to decrease the risk of cross contamination in the indoor environment. Especially after it had been documented that ventilation plays a significant role in decreasing spreading, several organizations working with ventilation and the indoor environment have been active in leading research and distributing information. The present webinar includes presentations of new guidelines, standards, or regulations from North America, Europe and Asia.

Building airtightness tests are now required or promoted in more and more countries, in particular for residential buildings. However, airtightness tests in high-rise buildings remain particularly challenging and uncommon. In addition to the difficulties of pressurizing any large-volume building and the wind issue that can be more pronounced at height, the stack effect can be particularly problematic.