The second lock is used for insurance, usually has only one locking bolt. Both locks must be protected by special steel plates, preventing them from drilling mechanism (Fig. 1). So protection of window openings, front door is securely locked. But we should not forget about the protection of window openings: no one will forcing an iron door to the apartment if you can climb through the window. The easiest way to secure them with powerful metal grates.
However, this simple design is far from ideal from the standpoint of fire security. Therefore it is better to choose another solution. For example, experts propleks Group of Companies, the largest Russian producer of pvc window-profile of Austrian technologies, it is recommended to protect Window shutters. Particularly interesting built their varieties. In this case, the box with protective cloth and rails are mounted directly to the windows (Fig. 4).
Thus, the whole system is one with window units, so that box, protective cloth and rails can not break or bend. Fig. 4 Nevertheless, the shutters are not a panacea, as the above method of mounting is only possible when the outer wall of the house have a sufficiently large thickness. Therefore, in many cases you need to take care of the resistance to cracking the windows themselves. There will be a plus and if rolstaven, after locking their locks can be podpilit outside. In addition, if an attacker, for example, managed to climb onto the balcony, or loggia, then it’ll have enough time to try to uncover the protective sheet, without attracting attention.