‘ColourLine’, an option with FAKRO DEF flat roof windows, enables outer cladding to be specified in any RAL colour from the Classic Palette. Whether to blend with a green roof, terrace landscaping or tiles on pitches up to 15°, thermally efficient glazing units provide an installed U-value as low as 0.76 W/m² - ideal for Passivhaus construction. White PVC interiors are ideal for bathrooms and wetrooms, while windows from 60 x 60 to 120 x 220 cm have a glazing area up to 16% greater than competitors’ windows of comparable size. All can be installed with an XRD upstand to add 15 cm height.