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Why Are Equal Sightlines Important?

(4 min read)

Quick FAQs

What are sightlines in windows?

Sightlines refer to the lines of sight that are created when you look out of a window. The size, shape and placement of the glazed panes and the frame affect the sightlines.

What are the benefits of equal sightlines in windows?

Equal sightlines are considered aesthetically pleasing as they create visual balance. Many period properties’ designs were based on symmetry, so equal sightlines can help you achieve an authentic appearance for your home.

How are equal sightlines created?

Equal sightlines are created when each section of a window is balanced and in harmony with the others. Equal sightlines can be created by fitting 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.

What are Sightlines?

Sightlines refer to the lines of sight created when looking out of a window. They also refer to the lines seen on the windows when looking at the property from the outside. This includes the frames, glass panels and glazing bars being in line.

The areas of visibility through a window can be affected by a number of factors such as the size, shape, and placement of the window. Architects, designers and window specialists all consider sightlines carefully in their work.

The term ‘equal sightlines’ usually refers to the horizontal line of a window, but homes can also have vertically equal sightlines. The sightline can also refer to the amount of window frame you see when you are looking directly at it. Narrow sightlines mean slimmer frames and conversely wide sightlines mean thicker frames.

For leaded glass and Georgian bar windows, symmetry is key, so equal sightlines are particularly important on these types of windows.

How Are Equal Sightlines Created?

Many consider equal sightlines desirable. You may see manufacturers boasting that a product offers ‘reduced sightlines’ or even ‘superior sightlines’. This means that all the dimensions of the glazed panels on a window are the same.

One way to create equal sightlines is to use dummy sashes (also known as dummy vents) to create equal sightlines between the fixed glass panels and the openings. Dummy sashes are made to look like the openings on the windows they are in line with, producing equal sightlines. This means that each of the windows in the home features a uniform, identical opening.

Another example of creating equal sightlines would be to create equal vertical sightlines. Fixed windows can be placed above other fixed windows and the same for opening windows. This creates a sense of balance within the design, as the shaping of each set of windows will be the same. Also see our article on non-equal sightlines.

How Important Is It to Have Equal Sightlines?

Some properties’ designs will benefit more from equal sightlines. Where unequal sightlines may look very obvious in one home, they may be less obvious in another. Equal sightlines help create a home that looks perfectly balanced and in proportion but they are not at the top of everyone’s priority list when choosing new windows.

Equal sightlines can ensure that all parts of a room benefit from an equal amount of light but this is unlikely to be very noticeable in most properties.

How Can I Create Equal Sightlines?

If equal sightlines are important to you for your home, you can consider the following ways to achieve them:

  • Choose windows with equal glass sizes: One of the simplest ways to create equal sightlines is to choose windows with equal glass sizes. This means that the height and width of the glass panes in each window should be the same. This will ensure that the sightlines are equal across all windows.
  • Use window grilles or mullions: If you prefer a traditional look, you can use window grilles or mullions to create the appearance of equal sightlines. Grilles and mullions are decorative elements that divide the window glass into smaller sections. They can be used to create a more symmetrical appearance and equalize the sightlines.
  • Install window treatments: Window treatments such as curtains, drapes, or shades can help to equalize sightlines. By covering the entire window opening, they can create the illusion of equal sightlines, regardless of the actual size or shape of the windows.
  • Plan the placement of windows: The placement of windows is another important factor in creating equal sightlines. If building a new property or an extension, try to place windows at regular intervals along a wall or facade. This will create a more uniform appearance and help to balance the sightlines.

Equal Sightlines in Summary

When investing in new windows or a glazed extension, the sightline is critical to your experience. Whether you choose to have equal or unequal sightlines very much depends both on the style of your property, and how you want to use your windows to get the best out of them.

Consider the sizes, shapes and proportions of the glass panels, the frames and any leading, and remember that the amount of light let in will be impacted by the thickness of the frames.

Need advice on the sightlines of your windows?

Work with your professional window provider to discuss your options and what will work best with the style of your property. Ask to look at examples and mock-ups of the finished design, and how it will look on your property.

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David Bryant
David Bryant
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Kate Hulbert
Kate Hulbert
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Nikki Wade
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Dominic Blood
Dominic Blood
This is the second time I have used Three Counties , a few years later and in a different house this time. It’s great to see the quality of the windows and workmanship have remained 5*. A stress free installation from start to finish, all windows installed have transformed how our 70s style house looks and now no worries of mould as a result of the old timber framed windows. The Installers who completed our job were amazing, and I mean amazing! Hard working, extremely skilful at their trade, polite and very tidy. Each day when they left they hovered up and left the place in the best condition they could. The whole process from the initial quote , measurements and dealing with the office team before and after the installation has been a true pleasure , if only all businesses were as efficient as this. Highly recommended for anyone considering new windows or any other products they provide and I won’t hesitate to use them again. Thank you Three counties!
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Kim Stevens
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I had some windows fitted a few years ago and have recently had a problem with one of the locking mechanism failing. I called 3 Counties, who had a base call out charge, where a lovely lady took my details, refered to my file and we agreed a date when the fitter would come out and inspect the issue. Paul arrived bang on time and was very helpful. He checked the window, confirmsd the issue and promptly fixed it there and then with a replacement part he had on board his van. He was polite and knowledgable. Very efficient. Thank you 3 Counties.
samie dowling
samie dowling
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Ywain Martin
Ywain Martin
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Victoria Stone
Victoria Stone
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