AIVC - Air Infiltration and Ventilation Centre

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air tightness

Effect of building and installation design on PM2.5

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.

Airtight duct systems [a simple way of improving a building’s energy efficiency without increased investment]

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.

Blower door tests of a group of identical flats in a new student accommodation in the arctic

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.

Lessons learned on ventilation systems from the IAQ calculations on tight energy performant buildings

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.

Investigations on the effects of airtight performance improvement and energy consumption of insulation retrofit in detached houses

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. 

Improvement of air tightness of communities

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 use of building own ventilation system in measuring airtightness

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.

Ventilation and RH control in museum showcases

Museum showcases represent a peculiar confined space were ventilation and indoor climate conditions play an important role. Conservation of the works of arts, in fact, requires a control of the environmental parameters, with a tolerance usually far tighter than that required for assuring the comfort of people.

Air Tightness of Ventilation Ductwork Equipped with Joints

The average air tightness of the ventilation ductwork in France is rather poor, corresponding toa 3A class. This is mainly due to air leakage in the fittings. Because of difficulties encounteredduring the implementation as lack of space, access problems or short time to proceed theinstallation, these fittings are not sealed enough, with mastic or adhesive tape.In order to limit this risk of leakage and to limit sealing operations on site, manufacturerspropose components equipped with joints. Some years ago, CETIAT has tested in itslaboratories different kind of such components.

Demand controlled ventilation applicable for any air tightness level and occupancy ?

The Dutch housing stock consists for about 70% of single family houses with an average N50 of about 7-9 ACH and for 30% of apartments with an average N50 of about 3-4 ACH.New single family houses are much more airtight. In the period 1970 to 2000 the air tightness increased to an N50 of about 3 - 4 ACH. Apartments have nowadays about the same or a slightly better air tightness then before 1970.Another trend is the downward tendency of occupant numbers per dwelling.