Explaining The Difference Between Flush Casement Windows & Non-Flush Windows

Explaining The Difference Between Flush Casement Windows & Non-Flush Windows

When a customer comes to one of our Design Centres to browse our different window displays, they will often turn to an advisor for clarification of what separates a flush casement window from a standard casement window and vice versa.

The ‘flush’ title denotes a window that has a completely flat surface due to its window sashes being exactly flush with the window frame.

Whereas, a non-flush casement window, or profiled casement window, has window sashes that ever so slightly stretch past the window frame.

Observe the two windows from side-on and you will see the distinction.

And here’s some added background on the two that you may find helpful:

What is their backstory?

The first flush casements were developed over 200 years ago using timber, so they date back to the 19th century. Almost every house of the Edwardian, Victorian and Georgian periods with flush casements has timber-constructed designs.

Non-flush casements can be traced back even further, to the 18th century, and are still to this day the most popular window design.

It was iron that they would be built from, rather than timber and way before the creation of UPVC and advancement of aluminium, by blacksmiths.

A grey sofa and parasol

Why are flush windows so in vogue again?

We’d like to think that we have had a hand in that, as we reacted to a growing desire for windows with a different kind of aesthetic by rolling out our Lusso aluminium flush windows.

A traditional timber flush window provided the design template for the range, so that’s why it has the elegant, simple lines that you’d historically associate with classic flush casements.

The easy-care aluminium profile makes a Lusso flush casement extremely secure and highly energy efficient.

A grey flush casement window

Which will best complement my house?

Because flush UPVC windows match the proportions and styling of original flush casements so successfully, they often receive the green light from planners for installation in properties within conservation areas.

The perfectly symmetrical profile of flush sash windows is also compatible with contemporary residences and new-builds, particularly when they are finished in a Matt Black or Anthracite Grey.

There are very few property types that casement windows won’t suit as they have such a versatile and adaptable style.

A grey bay casement window

Don’t hesitate to come and have a look at our Lusso and Portofino flush casements and non-flush casements in person to see which you prefer. Directions to all five of our Design Centres can be found here.


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