Applicability of a simple and new airtightness measuring method and further comparisons with blower door measurements

Abstract

Abstract 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 several 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. Current methods for airtightness measuring are too expensive and time consuming to make this feasible. A method with a new device, the AirTightnessTester (ATT), is proposed. By using the buildings ventilation system, a reduction in price and time can be achieved. The ATT measures in compliance with RESNET-380-2016. The ATT makes use of the ventilation system of the building. It will be explained when and how the ATT makes use of a ventilation system. We have looked at the different ventilation systems that are commonly used in new housing projects in somewhat more detail to analyse the feasibility of our method in practice. It is concluded that several systems can be used as they are now. Some ventilation systems cannot be turned on and off easily. For these ventilation systems a setting switching method has been developed. The theory behind this method, and some preliminary results using this method will be presented. To validate measurements with the ATT, comparisons have been done to the blower door. Preliminary results were already presented during the 2018 AIVC conference but further validation was still necessary. The measurements with the blower door are multi-point measurements and are all done in compliance with ISO9972. The measurements done with the ATT are all single-point measurements. The comparisons are made with the blower door, because since it is the most used method for airtightness measuring. To get a fair comparison, the uncertainty of both methods is taken into account. Overall the blower door and the ATT give show similar results for the airtigthness. In 23 of the 37 measurements it was found that the measured air leakage with the ATT was slightly higher than the measurement compared to the result with the blower door. When switching between a low and a high flow, it was found that 10 out of 12 measurements with the ATT were higher.