The safety feature in case of fire is an extremely discussed matter at the moment in the European Union by various groups of specialist, the Community authorities making real efforts to update the legislation and to harmonize the national norms with the new security requirements, imposed by the architects and beneficiaries. There were many cases in recent years, when measures to prevent disasters in this category proved to be insufficient, and the immediate results were constituted by significant property damage and loss of human lives. A complete elimination of such a risk represents an almost impossible goal at least at the current level of technologies, but it is expected from specialists in the sector more sustained efforts to improve passive and active measures taken for the prevention and limitation of the destructive effects of fire. Such steps are held permanently in most European and North American, although often there is an excess of eagerness of authorities which could affect the activity of entire industries if the changes of the rules are applied exactly as they are proposed by some persons who have not all the necessary technical  knowledge. A correct t effort, however, is more necessary than ever, being compulsory a balanced approach which to take into account all variables of this equation and to precisely identify those solutions presumptive to have the desired effect - namely minimizing risks and increasing defense against such disasters. In the industry of thermal insulating joinery, the various requirements of performance required to obtain the desired characteristics of heat and sound insulation, such as, for example, impermeability to rainwater, air tightness and sound insulation involves, unfortunately, the assumption of some compromises in the matter of fire behavior. Such an alternative is however not acceptable and the EU legislation requires that all materials used in sealing the enveloping structures meet a sum of requirements to ensure an optimal behavior in case of fire.