Blast load represent an exceptional condition which is usually neglected in the design of ordinary buildings. Recent terrorist attacks, however, have shown that explosion can typically result in massive damage or failure of buildings or part of them, with severe number of injures. In this regard, windows, fenestrations and facades represent the most vulnerable part for civil engineering buildings, and the first defense for occupants. Major challenge derives from secondary effects due to glass debris and fragments, which are propelled at high velocities and strike human bodies. The hazard increases especially in the case of existing buildings and traditional windows, where appropriate protection levels should be guaranteed by means of external systems, security upgrades and retrofitting tools. In this regard, the paper addresses the problem of blast effects on traditional glazing windows, giving an overview on actual possible solutions and research outcomes.