airtightness

Noticeably higher concentrations of gaseous pollutants were measured in bedrooms than living rooms, and in winter than summer, where p-values were found to be of a stringent significance (average p = 0.008). PM2.5 concentrations were found to be exceeding the WHO 24-h average threshold of 15 µg/m3 in kitchens for the week-long monitoring time (92% in winter, 51% in summer).

This article follows a first publication presented at the AIVC2022 conference (Handtschoewercker, 2022), with the preliminary results of the RENOVAIR project, that studies the impact of energy renovation works on social housing on the comfort and health of occupants when no requirements are given on IAQ, ventilation and airtightness performances. 

The global demand to improve the energy performance of buildings has led to greater air tightness and uncertainty in the ability of natural ventilation to maintain adequate indoor environmental quality. A monitoring campaign was carried out to evaluate the long-term indoor environmental quality across a year-long period in energy-efficient Irish dwellings.

Controlling air infiltration is crucial to ensure thermal comfort, optimal performance of ventilation systems, and the overall energy efficiency of buildings. The quantification of the overall airtightness of the building envelope, often conducted through pressurization tests, has been widely used. In addition, IR thermography is a valuable complementary tool for identifying and locating air leakage paths.  

Buildings energy renovation is a major priority in most European countries in order to achieve a fully decarbonized building stock by 2050. In France, 7 million homes are poorly insulated and 14% of French people feel cold in their homes. The government has thus implemented an ambitious plan to scale up energy-efficient renovations of buildings to achieve carbon neutrality by 2050 while also pursuing a social objective of combating energy precarity. 

This study utilized a CONTAM simulation to assess the effects of airtightness improvements in TNPI rooms. Sobol sensitivity analysis was used to evaluate the impact of building envelope elements on pressure differentials and contaminant dispersion. Results showed that inter-room penetrations, ward doors, and ward ceilings significantly influenced differential pressure, while exterior walls and inter-room penetrations predominantly affected contaminant dispersion.

Ensuring the airtightness of building envelopes is crucial for enhancing the energy efficiency of buildings. The prompt detection of leaks is essential, particularly when undertaking building renovations. Consequently, efforts have been made in recent years to implement new measurement techniques that facilitate the rapid, straightforward, and wide-scale identification of leaks in building envelopes. Two notable methods are the use of acoustic and thermographic technologies.

The WTA-Leaflets (International Association for Science and Technology of Building Maintenance and Monuments Preservation", (WTA)) provide recommendations on how a defined quality of building airtightness can be achieved when renovating existing buildings. These recommendations are guidelines that support planners, builder and quality inspectors involved in construction in their implementation. 
The leaflet series consists of 3 parts: 

All new dwellings in England and Wales are required to undergo a model-based overheating risk assessment prior to construction. An important model input is the building infiltration rate, which is usually estimated using a conversion factor on the dwelling airtightness. There is a paucity of evidence regarding the reliability of these methods in summertime. This aim of this paper is to provide new evidence on the relationship between airtightness and infiltration during summertime.