airtightness measurement

The purpose of the article is to introduce the condition of airtightness measurement market of large buildings in the Baltic states and in some European countries.

There are also considered national building norms of envelope airtightness and measured values.

Based on the measurement results of large buildings (more than 4,000 m³ volume according to ISO 9972-2015) the article assesses compliance of building norms of some countries with the actual building envelopes and the implementation of their controlling and stimulating functions.

Purpose of the work

Involve constructors and administration in the importance of BlowerDoor Test in large buildings.

Method of approach

Airtightness measurement. Conducting a BlowerDoor Test according to EN13829.

Content of the contribution

Mandatory building airtightness testing has come gradually into force in European countries, mostly because of the increasing impact of building leakage on the overall energy performance of low-energy buildings.  Therefore, because of related legal and financial issues, the reliability of the airtightness test has become a crucial issue and has raised the question of the fan calibration process. 

Uncertainties in airtightness measured using fan pressurization test should not be defined by the scattering of the points around the line defined using ordinary least square method anymore. Its definition requires first to know the uncertainties in pressure and airflow measurements. This works aims at quantifying one of the component of the envelope pressure uncertainty: the uncertainty in zero-flow pressure approximation due to short-term fluctuation of wind speed and direction.

This paper presents the results of a series of 30 fan pressurization tests in reproducibility conditions performed within a period of 10 days in October 2017. The tested unit is a newly constructed unoccupied apartment in Brussels. These results make possible to compare different regression methods and evaluate the impact of pressure stations chosen for these regressions.

Since January 1st, 2018, airtightness testing has become implicitly mandatory for every new residential building in Flanders. There is no minimum requirement for airtightness. However, there is one for the global performance of the building envelope (S-level, taking into account thermal insulation, airtightness, solar gains, etc.), and a poor airtightness would jeopardize the chance to reach the required S-level.

Mandatory building airtightness testing has come gradually into force in the UK, France, Ireland and Denmark. It is considered in many other European countries because of the increasing weight of the energy impact of building leakage on the overall energy performance of low-energy buildings.
This study analyses recent developments in 10 Europeans countries on the following aspects:
- requirements regarding building airtightness in EP- regulation
- requirements in specific energy programmes
- airtightness testers schemes

The paper presents airtightness measurements results of the multi-family building. The tests were carried out in several ways, the results obtained by different methods were compared and the likely reasons for the discrepancy of results were indicated. The object of measurements was a six storey building with 47 dwellings equipped with natural ventilation. Air inlet to the rooms through the window trickle vents controlled by relative humidity of air. Air is extracted through vertical extract ducts made of ceramic blocks.

Accidental dispersion of toxic gas clouds may occur around industrial platforms or during hazardous materials transportation. In case of such a toxic risk, the best protection strategy is to remain inside a building and seek refuge in an airtight room identified as “shelter” until the toxic cloud has finally been swept off. This strategy called “passive shelter-in-place” also includes obstructing all external openings and turning off all mechanical ventilation systems

There are often practical limitations to measure the airtightness of a multifamily building as a whole as described in EN 13829. The building may be too large; the floors may not be connected with an internal airflow path; or there may be large leaks in the stairway.