The issue of protection of residential buildings against gas mixture explosion in which glazing windows are considered as safety structures (SS), which are mounted in the depth of a window aperture, is considered. It is shown that when the fastenings, fixing the window frames to the wall of the building, are destroyed, the SS starts moving inside the aperture, the area for the gases discharge does not open, and the explosion occurs in the conditions of a sealed volume. It has been established that for small spaces (30–150 m 3 ) the rise time of pressure in an internal explosion is comparable to the movement time of the SS inside the aperture. The magnitude of the pressure increase during the movement of the SS inside the aperture has been determined. A dimensionless parameter has been selected that determines the pressure increase from the moment the SS begins to move until the aperture opens for gas outflow. It has been shown that twofold or tenfold pressure increase can cause destruction before its discharge. An expression for determining the speed of the SS at the moment of opening the aperture has been obtained, and this speed mainly determines the rate of pressure discharge due to the gases outflow. It has been established that the pressure increase during the movement of the SS inside the aperture exceeds the pressure increase pressure after the opening. It was revealed that when testing and designing SS, it is necessary to take into account the depth of SS embedment depth in the aperture, especially for residential premises, the volume of which does not usually exceed 120 m 3 .