Quickslide, manufacturer of the Renaissance Window System, has received recognition from the British Standards Institute for vertical sliding sashes and casement windows that achieve the highest possible energy ratings. <br> <br> Renaissance windows achieve an A rating under the Window Energy Rating scheme, as devised by the British Fenestration Rating Council. Windows that are rated C and above comply with the latest revisions to the Building Regulations the company explains, and A-rated windows typically have U-values of just 1.4. <br> <br> Quickslide also says that its Renaissance windows are made using double-glazed units which comprise Saint-Gobain Glass’s Planitherm Total+ glass, creating an insulating window that has fewer cold spots and draughts, less condensation, and improved noise reduction. Furthermore, the glass is not tinted like other low E glass on the market which allows for better natural lighting<br> <br>