The windows themselves can not create a frowziness: the metal-plastic window either is in a hermetically sealed condition, or allows air to penetrate into the room, being in ventilation mode or being completely open. And the so-called myth about the frowziness is due to the fact that everyone is accustomed to the non-tightness of the old window frames that let air through, regardless of whether we want it or not, thereby allowing the windows to “breathe”. And in winter, by the way, also, that previously caused regular seasonal sticking of windows with a paper tape.
Tightness – one of the distinguishing features of modern metal-plastic windows. The tightness provides a comfortable climate in the house due to the lack of blowing, drafts, and freezing.
Due to the fact that the plastic windows prevent the spontaneous flow of air into the room, it is necessary to regularly carry out ventilation (several times a day for 15 minutes is quite enough). Another way is to install fittings for micro-ventilation. In this case, even in the cold season, it will be possible to leave the window open for several millimeters, which will allow fresh air to enter the room without risking of making it cold.