envelope

This paper describes two recent applications of aerosol sealing techniques in buildings for improving indoor air quality and reducing energy required for heating, cooling, and ventilation. One application applies a commercially-available duct sealing technology, which has typically been used in single-family applications, to large-building exhaust systems. The initial leakage rates, percent leakage sealed, and issues encountered are presented for several large buildings.

From 2006 till 2012, the 2005 energy performance (EP) regulation (RT 2005) did not entail any obligation to justify the envelope airtightness level. As a consequence, asking for the certification of airtightness quality management approaches was a voluntary request from constructors. Thus, they might be allowed to take into account a better-than-default value into the thermal calculation. Since 2012, French 2012 EP regulation (RT 2012) requires building airtightness level to be justified, with two ways of justification.

Accidental releases occurring in industrial platforms or during transportation of hazardous materials can entail the dispersion of toxic gas clouds. In case of such an event, the best protection strategy for people is to identify a shelter in a nearby building and stay in this room until the toxic cloud has finally been swept off.

The 2012 French thermal regulation will include a minimum requirement for residential buildings envelope airtightness, with two options to justify its treatment: a) measurement at commissioning or b) adoption of an approved quality management approach. This paper describes the qualification process for air-tightness measurement authorized technicians when their results are to be used in the EP-calculation method. Our analyses underline the importance of the qualification process to ensure homogeneous measurement practice among technicians.

It is foreseen that the 2012 version of the French regulation will include a minimum requirement for the envelope airtightness of residential buildings, with two options to justify its treatment: a) measurement at commissioning or b) adoption of an approved quality management approach. This paper describes the qualification process for authorizing technicians to conduct airtightness measurement when the result is to be used in the EP-calculation method. It also discusses the requirements set for approved quality management approaches.

Infiltration has traditionally been assumed to contribute to the energy load of a building by an amount equal to the product of the infiltration flow rate and the enthalpy difference between inside and outside. Application of such a simple formula may produce an unreasonably high contribution because of heat recovery within the building envelope. Previous laboratory and simulation research has indicated that such heat transfer between the infiltrating air and walls may be substantial.

The Energy Performance of Buildings Directivementions that each member states' energyperformance (EP) calculation methodology mayinclude envelope airtightness. In fact, manymember states have included envelopeairtightness in their EP calculation method.Many countries have also specific requirementsfor ductwork airtightness. However, they seemto be unequally successful in achieving a markettransformation. This paper describes themechanisms that have been used in somecountries, with a special focus on success storieswhich could inspire other member states.