Mass Loaded Vinyl (MLV) is a versatile and economical soundproofing content for windows, made from PVC and vinyl using a heavy product such as barium sulphate or calcium carbonate. It’s a sympathetic, classy and really successful retrofit Option, but In relation to secondary glazing, there’s lots to take into account. https://windowinsulation58454.timeblog.net/74475994/how-much-you-need-to-expect-you-ll-pay-for-a-good-acoustic-windows