Update of the spanish regulation regarding ventilation and infiltration: analysis, comparisons and repercussions

The Spanish Technical Building Code is one of the three royal decrees that were approved in Spain as a consequence of the transposition of the European Directive on the energy performance of buildings (2002/91/EU) [1]. One basic document of the Technical Building Code deals with the limitations in the energy demand of buildings. Nowadays, due to the recast of the European Directive on the energy performance of buildings (2010/31/EU) [2], a revision process of the current regulations has begun, starting with the Technical Building Code, with its first revision envisaged for 2012. In this article we, as collaborators in this updating process, describe and analyse the main changes regarding ventilation and infiltrations that the updated Technical Building Code (TBC) is going to introduce. These main changes were classified in the next aspects, the calculation methodology, the ventilation technologies that can be considered, and the default values and the data that the user can supply to assess its particular case. The article compares the ventilation required in Spain with the mandatory values in other 16 European countries. Finally, the mean air infiltration values are compared to the values of the EN 15242:2007 [3] and to measured air infiltration values in actual Spanish dwellings.