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Flush Sash


Flush sash casement windows are the latest generation of uPVC windows. They offer the realism of a traditional pre-1932 timber window combined with 21st century thermal benefits.


Many property owners require a traditional timber window frame, sometimes due to planning or environmental restrictions. Liniar Flush Sash windows can be mechanically jointed, for an authentic timber appearance.


Timber frames tend to be expensive, need regular maintenance and can be difficult to replace.


Liniar recognised the need to develop a casement window frame that would fit into any property where the sash fitted flush into the frame – and which could be foiled to look like traditional timber or to offer a sleek, contemporary finish.


Using cutting-edge technology and machinery, Linear extrudes the lead-free uPVC frames used for its products and distributes them to a nationwide network of retuable window fabricators. These fabrication experts make linear flush sash uPVC windows to our precise and exact pattern. Glass is added, and the fabricator then either fits the product themselves or supplies them to independent window installers.

Liniar flush sash windows, like the rest of the Liniar EnergyPlus window range, are A+ rated. They offer a lower cost with higher thermal benefits, in addition to being fully secure.


Available in a sculpted profile with a flush finish on external faces, 28mm double or triple glazing, internally beaded, and a wide choice of opening configurations, colours, finishes, hardware and glazing.

British Made

Liniar lush sash window frames are made from lead-free PVC which is extruded in the UK. The factory boasts the largest PVC mixing plant in the UK. Continued investment keeps Liniar at innovation forefront.

Thermally Efficient

The revolutionary profiles used by Liniar casement windows are far more thermally efficient than traditional uPVC window profiles.

We make sure the heat stays where it belongs - inside the home!

Ultra-slim Sightlines

Liniar's flush sash uPVC windows are less frame and more glass, meaning a much more attractive window and letting in the maximum amount of natural light. High tech-tech design and engineering for every home.

Environmentally Friendly

Liniar flush sash uPVC windows are fully and easily recyclable at the end of their lifespan.

 Also, all Liniar's window frames are, and have always been, 100% lead-free - far ahead of legislation.

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