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Sightlines

Searching for window products online, you’ll soon come across manufacturers boasting of a particular product offering ‘reduced sightlines’ or, perhaps, the even more vague ‘superior sightlines’. What are these ‘sightlines’?

Combining fixed sashes with opening sashes on a window unit usually means that the upper and lower glazing lines are uneven – because the opening sashes have a smaller glazed area.

Equal sightlines are aesthetically desirable on many houses. The effect can be achieved by specifying flush casement windows – examples include Residence Collection R7 / R9, Deceuninck Heritage and Evolution windows.

Flush casement CROP not straightened Admiral Windows Oxford

Flush casement window – the upper and lower glazing lines are level.


A more economical way of achieving equal sightlines is to fit dummy openers to non-opening sashes of a standard (non-flush) window so that the glazed dimensions of fixed and opening sashes are the same.

012 double casement equal sightline_astragal bars_Admiral Windows Oxford

uPVC window with dummy opener, giving straight upper and lower glazing lines.


Aluminium window frames are slimmer than uPVC or timber frames – hence they offer ‘reduced sightlines’. This means that you’ll see less frame and more glass.

alu casement Sumertown_Admiral Windows Oxford (3)

Aluminium casement window. Compared with the opening sashes, the fixed central sash has a slightly larger glazed area . Hence, while this window unit gives ‘reduced sightlines’, these are not ‘equal sightlines’!


Admiral Windows has over 30 years experience fitting replacement windows around Oxfordshire. We’ll fit the right windows for your home and for your budget – and we’ll do a proper job. For more information, please visit our website admiralwindows.co.uk – or give us a call on 01865 788333.

Admiral logo and telephone with FENSA logo
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