The vertically sliding sash and case window takes some beating. You can open it at the top to let out stale air and at the bottom to get a good blast of fresh air. Properly installed it blocks as little daylight as possible. Before the advent of float or plate glass the smaller panes required glazing bars or astragals which were deliberately made as slim as possible so as not to obstruct the light.
Modern improvements include draught stripping around the opening sashes which also helps them to glide freely and double glazing, particularly of the “slimlite” kind which can often be retrofitted into existing windows. Also there’s the clever system of Simplex hinges that makes it possible to clean a sash and case window relatively easily from the inside. By comparison casement, pivot and tilt-and-turn windows are generally not nearly as convenient or capable of providing finely controllable ventilation.
But there are other neat ideas adopted in continental Europe such as the concealed roller shutter that disappears into a hidden box above the window frame and slides down on slim runners on the outside of the window providing a complete blackout, insulation and security at night.
Director, Building Surveyor