I'm making a secondary glazing panel myself (not with magnetic strips) out of plastic (acrylic or the likes of) and with a wooden frame around the edge to secure to the window. Some of the prices are quite reasonable (~£60 for a 1300 x 1800 panel), so I prefer the idea of this rather than the very expensive aluminium kits that you can get. Whilst doing this, I suppose I could create a double layered glazing kit e.g. two pieces of acrylic with a ~10mm gap between. Would this be even more efficient, or a waste of time do you think?
If as a secondary glazing probably marginally if sealed well, making your own double glazed unsealed units would be a mistake.
slot 18 x 45 par timber to accept perspex. The bigger the gap the better for sound and heat. build the subframe and slot perspex into slots then when not needed leave subframe in and remove perspex
Double glazing usually has 2 different thicknesses of glass (4 and 6 mm) for better accoustic dampening the different thicknesses dampen different frequencies........ I think . They usually contain a desiccant around the seal to remove the moisture in the cavity an interesting project for DIY good luck if it all goes well will look out for you in eBay