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Why is standardization at EU level so important?

Today most companies (consultants, manufacturers and contractors) work internationally. From their point of view it is preferable to have internationally accepted calculation methods and input data for the energy efficiency of buildings...
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Why isn’t it possible to download the CEN standards from a website (e.g. www.iee-cense.eu)?

Standards are copyright protected property of the publisher (CEN , ISO etc.) and not part of the public domain. Question submitted by: Dick van Dijk (TNO, The Netherlands) Anwered by: Dick van Dijk, TNO and Jaap Hogeling, ISSO (The...
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What to do if I have questions about the use or technical content of a CEN standard to support the EPBD?

In general questions on standards could be answered by the National Standard Body helpdesk. They may also refer you to their national experts who have been involved in the preparation of the standard on a national or international level....
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Why is the use of the CEN-EPBD standards not mandatory for Member States?

General The commission supported the development of the CEN standard by giving a mandate to CEN to produce the standards needed to support the implementation of the EPBD. It will be beneficial for Europe if all Member states use these...
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What is the relation between the EPBD and the developed CEN standards to support the EPBD?

The developed standards reflect the requirements of the EPBD as given in the different articles and the annex. The procedures as given in the standards meet the essential requirements as set out by the EPBD. Note that the EPBD is an...
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What is in the set of EPBD CEN Standards?

The set of CEN-EPBD standards consists of 43 titles or parts and can be grouped as follows: The building physics standards, e.g. describing the calculation of heat transfer by transmission and ventilation, load and summer temperature,...
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In which languages are the CEN standards available?

It may be that although the National Standard Body produced a national language version, the standard will always be available in English (the official text), in many cases also a French and German version may be available. The French...
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Are the calculation procedures fully harmonised?

To support the open EU market, more and more standards have been prepared as ENӳ. For building products this is even a requirement based on EU mandates to CEN according to the EU-CPD (Construction Product Directive). To stimulate an open...
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What are these and where can one find updated information on the infringement procedure regarding EPBD?

Details and full Information on infringement procedures can be found here: ec.europa.eu/dgs/energy_transport/infringements/index_en.htm For specific information regarding infringement procedures in relation to the EPBD (2002/0091),...
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What is the present status and where can one find updated information about this revision process?

Information on the recasting technique by the European Commission is available here: http://ec.europa.eu/governance/better_regulation/codif_recast_en.htm For information on the main problems, main policy objectives, and policy options,...
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Can the calculation method for the overall transmission and ventilation heat loss coefficients, which is presented in EN ISO 137

Yes, but some of the required input data may not be available at reasonable costs. For those cases default values may be provided at national level, e.g. as function of type and age of construction. Question submitted by: Dick van Dijk (...
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Many CEN-standards are ISO-standards, e.g. EN ISO 13790, 6946, 10077 and 14683. How can these standards make reference to the se

If an ISO (International Organization for Standardization) standard is also an EN ISO standard, then it is a European standard just like any other EN (European) standard. As illustrated in several CENSE Information Papers, e.g. P92 or P94...
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why was the term “heat transfer” introduced instead of “heat loss” in the CEN standards to support the EPBD?

Heat is lost from a building or building part by transmission or ventilation, as a result of a positive temperature difference between the indoor and outdoor (or other) environment. However, if the indoor temperature of the considered...
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Does the airtightness depend on construction type?

Measurements usually show that light (e.g., timber-frame or steel) constructions are leakier than massive construction, but this is not bound to be. In fact, PassivHaus houses are often light constructions and are very airtight. The...
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What is the effect (extent) of the aging process in the airtightness performance?

There is little information on the subject at the moment. A study referenced in a paper written by Erhorn et al. and presented at the 2008 AIVC conference shows airtightness values of 31 “Passivhaus” houses at commissioning and 2 years...
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How is a pressurisation test performed on single apartments?

The airtightness measurement of single apartments is usually performed the same way as in individual houses. Therefore, there is no specific protocol to balance the pressure between the apartment under test and other apartments. Different...
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How do you measure the airtightness of multi-family buildings?

Measuring or evaluating the airtightness of multi-family buildings is challenging as there may be technical and practical difficulties that prevent from pressurizing the whole building. These difficulties include for instance building...
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Why are there different indicators (n50, q50, w50, etc.)?

Now in Europe, many countries have adopted the n50 value (i.e., the leakage flow divided by the volume) for their EP regulation while others (e.g., Belgium, France, UK) use the envelope area normalisation. The rationale behind this latter...
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Is it possible to compare airtightness measurements between the Member States?

To some extent yes. A collection and analysis of some data collected through the ASIEPI partners has been presented at the 2008 BlowerDoor conference (Papaglastra et al., 2008). However, caution should be exercised when comparing...
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How do you deal with envelope airtightness value in energy losses calculation?

There are three major ways to estimate this impact: - the simplest is to evaluate the infiltration losses based on a rule of thumb established by Drubul in 1988 (*) and suggested by Kronvall (**) in 1978. The rule says that the...