The significance of leakages – Problems of evaluation and recommendations for action. Results from the FLiB research project

Airtightness/air permeability are inseparable from leakages and their detection, categorization, or evaluation. The diverse contexts due to the main construction methods, structures, materials used, individual conditions on site for each building, and the perspectives of the different disciplines regarding airtightness, make it hard to take quick...

Airtightness of multifunctional tapes

For several years, multifunctional tapes have increasingly been used for the airtight installation of windows in new buildings or renovation projects. The adhesive tapes are wrapped around the window on three or four sides. After the installation of the window, the tape expands and closes the joints between window and reveal...

A legal evaluation of leakages – Arguments beyond building physics

Leakages in the building envelope may cause severe damage to a building and thus inevitably become an issue not only for building physics, but also for the law. In the case of such legal disputes, the different perspectives of scientists and lawyers frequently turn out to be a problem. This is further acerbated by the different levels of...

Recommendations for the optimal and lasting sealing of joints from a hygro-thermal perspective

Windows according to the Passive House Standard 2016 require a ten times more airtight airtightness class (EN 14351) [1] than around 1990. The installation layer of the windows is constantly moving closer into the area of the insulating layer with possibly moisture-sensitive materials. Therefore, joint sealing of construction and connection joints...

Individual and guard-zone measurements in apartment buildings - Measuring results

With the German Energy Savings Regulation EnEV 2014 the legislators have qualified the requirements for large apartment buildings (VL > 1.500 m³). In addition to the air change rate (n50 ≤ 3,0 h-1 or n50 ≤ 1,5 h-1 depending on the ventilation technology used) the envelope-based air permeability (q50 ≤ 2,5 m³h-1m-2) is now also required...

Planning and implementing airtightness with an airtightness design

According to the legal regulations and the rules of technology (as generally accepted) new buildings are to be constructed permanently airtight. In order to do so, an airtight building envelope has to be carefully planned prior to the actual construction process. This is how it is stipulated in the German Industrial Standard...

Airtightness in North America seen from Building Physics Viewpoint

Environmental control (heat, air and moisture flows and their effects) started 90 years ago on Prairies of Canada and USA. It has always been based on occupant’s interest in a better indoor environment and driven by builders. More recently, when energy efficiency and durability considerations became part of socio-economic...

Flaws in airtight layers – A “holistic” research approach for building practice

Stricter requirements, e.g. for thermal insulation and moisture protection, as well as progression in energy-efficient building have led to the development of special building materials and metrological equipment. Over the last two decades, airtightness measurements, frequently also called “BlowerDoor tests”, have become increasingly...

There is a draught, so what? Robust, tried and tested solutions ‒ Airtightness designs of structural elements and building components

Proposals for solutions in accordance with German standard DIN 4108 Teil 7 What does real life look like? What can actually be solved? Challenges, interface issues between the different trades and crafts, and possible suggestions for solutions. The industry-wide educational and training center of the Baden-Württemberg...

Infiltration through leaks? A careful analysis of minimum air change according to DIN 1946

Can the minimum air change in naturally window-ventilated units be covered only through leakages? In general, the infiltration airflow rate is dependent on meteorological conditions, especially wind pressure on the building / unit, and with regard to thermal effects, the temperature differential between the interior and the exterior...

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