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True double casement windows

bryanbl | Posted in General Questions on

I am wondering what the options are for high performance double casement windows – or if this is even possible given the sealing details at the interface between the two sides.

Several manufacturers have stated they offer ‘double casement’ but upon further questioning, it is two single casements mulled together.


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  1. bcade | | #1

    I can't speak to high performance options, but what you're after is called a French casement. They're not as common, and are considerably more expensive than two normal casement windows mulled together. Presumably will not seal as well as a traditional casement that uses compression seals all the way around.

  2. Expert Member
    Michael Maines | | #2

    I have not seen French casements in a European-style frame, but Loewen has triple-glazed, traditional-looking French casements that probably seal as well as anyone's.

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