BADA

This ebook, produced by TightVent Europe, includes a number of publications from the Intelligent Energy Europe programme and its predecessor, namely from the ASIEPI project, SAVE-AIRWAYS, and SAVE-DUCT projects.

This ebook includes a number of selected papers from the 33rd AIVC-2nd TightVent conference held in October 2012 in Copenhagen.

The 2002 Energy Performance of Buildings Directive (EPBD) already indicated the potential importance of airtightness. With the 2010 EPBD recast and its ambitious 2020 targets, there is even more pressure on these aspects since for most European climates and countries, good envelope and ductwork airtightness levels are necessary to achieve nearly zero-energy buildings.

The building airtightness is essential to achieve a high energy performance. In most countries however, it is not mandatory to measure the airtightness. In the Netherlands it is common practice to just take a couple samples in a housing project. These samples do not give a good indication for all the buildings in a project. It is therefore important to measure the airtightness of all the buildings.

Previous studies have compared the airtightness measurement of test enclosures utilising both the novel Pulse technique and the conventional blower door method.  Discrepancies between results of the two test methods were observed and it was concluded that differences either caused by wind or blower door installation integrity would have had an impact upon the results.

Building airtightness is a critical aspect for energy-efficient buildings as energy performance of a building can be reduced significantly by poor airtightness. The Pulse technique has been regarded as a promising technology, which measures the building airtightness at a low pressure of 4Pa by rapidly releasing a 1.5-second pulse of air from a pressurised vessel into the test building and thereby creating an instant pressure rise that quickly reaches a “quasi-steady” condition. However, questions have often been asked on the test viability due to the nature of the test.

Requirements for measuring the building airtightness have been proposed and included by many countries for national regulations or energy-efficient programs to address the negative effect of poor airtightness on building energy performance, durability and indoor environment. The methods for measuring building airtightness have continuously improved and evolved over a number of years.

Heating energy in buildings represents a significant proportion of the total global energy consumption. Uncontrolled airflow through the building envelope contributes significantly to its energy losses.  

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. 

Various studies demonstrate a significant impact of ductwork leakage on the fan power consumption of ventilation systems. They have shown that the total energy used by fans can be reduced by 30-50% by improving the airtightness of the ductwork system. However, most of those studies focused on non-residential and multi-family buildings. This study focuses on single-family dwellings; specifically houses.