Glasses reflective in the spectral range of long-wave infrared radiation operate as heat mirrors. These glasses have found wide applications in architecture. Special thin film coatings on glass panes reflect long wave infrared radiation back to building interiors. The reflective thin films limit absorption of infrared radiation within the glass pane and reduce radiation heat losses of glazings. Heat losses of windows could be significantly limited with the coated glasses which are called low-emissivity glazings. The study of materials convenient for infrared reflective coatings, the optimal composition of thin films and their thicknesses is the main topic of the presented paper. The study is based on measurements of spectral characteristics of selected glasses and computer simulations of the thin film composition for applications of window infrared reflective coatings.