In contemporary sash windows, you're much more very likely to look for a spring harmony (or sash harmony) technique. This is a spring-loaded unit which counters the pressure of gravity, in outcome holding your sash window open up with no require for cords, pulleys and people metal counterweights.  Use weatherstripping: https://noise-reduction40502.bloggadores.com/34663654/not-known-facts-about-sash-window-draught-proofing