air tightness

The air tightness of eight apartment buildings containing six to eleven units each on three or four floors has been tested with and without guard-zone pressure, i.e. with and without consideration of internal leakages. The layouts of these buildings varied: two of them had no central stairwell, in two other buildings, only some of the apartments were connected to the central stairwell, and the third type had all apartments connected to a central stairwell.   During these tests, two to eight BlowerDoor systems were used simultaneously to create guard-zone pressure conditions.  

The airtightness of buildings is important for several reasons, such as being a prerequisite for low-energy buildings and for a healthy indoor air quality (without i.e. mould or radon). The airtightness of buildings can vary over time and investigations are made on these variations due to moisture induced movements in wooden constructions, and subsequent consequences, using both measurements and numerical simulations.

Combining heat recovery with natural ventilation is a relatively new topic of significant academic and commercial interest. The present study shows the performance of a recently developed Passive Ventilation system with Heat Recovery (PVHR) installed in a primary school building.

People spend more than 80% of their time indoors. In contrast to ambient air, no (legal) limits for indoor particulate matter exist, although there are WHO guidelines. In the Netherlands a measurement protocol to determine the PM2.5 in office buildings has been developed including 5 quality classes. However at the moment no simple guidelines or models are available which can support the design and in-use phases to predict the PM2.5 concentration in office buildings and schools.

Against the background of increased global demands for energy efficiency, property owners should raise the standards of ductwork systems for ventilation, heating and air conditioning. This would not only save energy, but also mean lower installation costs, shorter assembly times and better air quality thanks to less leakage. The importance of energy-efficient buildings will increase in the future, not only due to rising electricity prices, but also due to increased environmental awareness.

A new student accommodation for engineering students “Apisseq” was built in the town of Sisimiut, Greenland in 2010. Its purpose is not only to provide accommodation for students. Thanks to its complex monitoring system it enables researchers to evaluate the building’s energy performance and indoor air quality (IAQ) as well as performance of some single components. In summer 2012 a blower door test was performed on all 37 living units out of which 33 are identical single room flats and 4 are larger double room flats.

During the project QUAD-BBC, several ventilation systems have been studied in residential (individual house and collective dwellings) and non-residential (school, offices) and assessed by the evaluation of an IAQ multi-criteria.
These calculations have shown some typical evolution of pollutants in very tight low consumption buildings and can alert on some possible effects.

Recently, insulation retrofits of existing houses have been thought to be one of the effective measures from the viewpoint of global warming prevention. However, the overall reduction effects of environmental loads by the insulation retrofits have not yet been clarified. This study intends to accumulate basic data concerning the insulation retrofits and to promote the energy saving of existing houses. 

From the beginning of year 2007 the buildings in Finland must have energy efficiency calculations, which requirements are now part of Building Codes, based on European Performance of Buildings Directive. According the renewed code, being into the force from July 2012, air tightness number q50 cannot be more than 4 m3/ (h*m2). Better air tightness can be shown by measurements. The air infiltration must be calculated in compensation calculations based on air tightness number 2.0 m3/ (h*m2). The energy efficiency requirements caused an immediate response in the building sector.

The improvement of energy efficiency is the key issue after the energy performance of buildings directive came into the force in European Union countries. The city of Kuopio in Finland participate a project, in which different tools will be used and tested to improve the energy efficiency of public buildings. In this project there were pilot buildings e.g. schools. The other pilot school consumed much more heating energy than the other same type of school. Air tightness was measured using the own ventilation system of the building and by remote control from the central operation room.