From 8:12 in the YouTube clip above, you can observe a sheet of acrylic magnetic strip secondary glazing being removed and applied from/to a sash window.
What would you think about the idea of having this sheet of acrylic split along the horizontal at the meeting rail? There would therefore be two sections of acrylic.
It would mean the lower section of acrylic would only have to be removed if you wanted to slide the sash up to air a room, rather than a larger and more cumbersome section of perspex.
I wonder to what extent such a split would reduce the heat/sound insulation properties of the secondary glazing? If not a huge amount, then this may be acceptable in order to make the perspex less cumbersome. Any thoughts? Thanks.