Cannot open thoroughly, compared with double casement windows as you can find generally the size of 1 sash more than the window.  Pictured previously mentioned: Sash window grooved out study for draught proofing program. A router and 8mm straight flute cutter is accustomed to Reduce a neat, accurate groove. Plantation https://eyelash-extension-tweezer14566.blogchaat.com/36187786/sash-windows-no-further-a-mystery