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Slim Integral Mullion

The visible mullion between windows in some cases can be as wide as 250mm, which is nothing like the slim mullions on original timber windows. On triple window styles, where the centre sash slides and the two wings are fixed, thick sight-lines are even more obvious, negatively impacting on any authentic detailing.

The bespoke slim mullion measures just 99mm across the front face, which substantially reduces the overall thickness of the sight-lines. Double or triple sash windows no longer look bulky and will complement the period aesthetics of your home. The integral mullion is available as standard on Symphony and Vintage sash windows.

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Our MASTER INSTALLERS are a team of specially training craftsmen, chosen to deliver a quality installation of your Masterframe windows.