What are the standard window sizes in the UK?

6 min read Windows

Although windows can be created on a bespoke basis to suit the homeowner, they are also available in a number of standard window sizes.

A guide to standard window sizes

Knowing these standard window sizes is useful to anyone considering window replacement as you’ll know if the size you require is readily available. If you're looking for new windows, you'll probably realise that there are a number of consistent size options with each window material and style. The sizes are designed to fit the most common size openings on UK properties.

With this in mind, we’ve created this blog on standard UK window sizes to help any homeowner out there find out the window measurements specific to each window material and style.

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Standard uPVC window sizes UK

The average window size for uPVC windows depends on the window style that you're considering. Windows such as bay windows tend to be larger than sash windows and casement windows due to their specific design. Here's our guide to uPVC window sizes in the UK.

Standard uPVC window height

Tilt and turn windows

A popular choice for homeowners, uPVC windows are cost-effective, thermally efficient and easy to maintain. The standard window height for them starts at 450mm and goes up in increments of 150mm. We have listed the full standard window heights for them below:

  • 450mm
  • 600mm
  • 1,050mm
  • 1,200mm
  • 1,350mm
  • 1,500mm

Standard uPVC window width

White slimline windows and doors

The width of uPVC windows is not as straightforward as the height. This is because their frames were originally made to fit bricks that were 215mm long. However, uPVC window frames have also been made to fit bricks that are 300mm in length, in accordance with a directive from the EU. We have listed some standard window widths for them below:

  • 488mm
  • 630mm
  • 915mm
  • 1,200mm
  • 1,770mm

Standard thickness of a uPVC window frame

Standard uPVC windows are double glazed, which means that they’re fitted with two panes of glass. Between the two panes is a space that is around 12mm-16mm. This gives a standard thickness of around 20mm – 28mm for a uPVC window, which is too bulky for some homeowners.

Fortunately, however, our exclusive slimline uPVC windows are the perfect solution for anyone who wants to enjoy the benefits of a high-performance uPVC window without the thick framing.

Get a free no-obligation quote for replacement windows custom-designed for your home

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uPVC slimline windows with thin frames

Our exclusive slimline windows feature profiles that are similar in depth to single glazed timber windows. As a result of these slender frames, we’re able to fit them with 12% more glass than a standard window. The beauty of this being that the more glass there is, the bigger the passageway there is for light to enter your home.

Take a look below at our comparison of a standard uPVC casement window vs our modern uPVC thin-framed windows. They can be custom-designed to your home in a range of modern and traditional colours, wood effects and designs. You can choose to incorporate our decorative glazing and a number of window furniture elements to add the finishing touches.

Slimline vs casement

So, your home will feel better lit and more spacious, plus you can better appreciate any views of your exterior space. But, that’s not all; they’ve been awarded a Window Energy Rating (WER) of A+ so are as thermally efficient as any window you’ll find on the market. Therefore, you can enjoy a more comfortable home day by day for less.

Our uPVC Window Options

Find out more here about standard uPVC window frame thickness vs our slimline window range.

Standard aluminium window sizes

aluminium windowsDue to aluminium’s inherent strength, aluminium windows can be fitted with slender frames, similarly to our uPVC slimline windows. This means that the average aluminium window size features less frame and more glazing. The window measurements will depend on the window style that you are opting for, as styles like tilt and turn tend to be larger than a standard casement window.

The maximum and minimum sizes for the width and height of aluminium windows, however, are listed below:

  • Minimum width: 350mm
  • Maximum width: 1400mm
  • Minimum height: 300mm
  • Maximum height: 1500mm

Our Aluminium Window Options

VELUX windows in a range of sizes and designsWhite VELUX window square

Modern VELUX windows are available in a number of sizes, styles and designs to accommodate any installation. Whilst they are normally offered in a set range of sizes, they can be custom-designed to fit more unique spaces.

The beauty of VELUX skylight windows is that they'll let in plenty of natural light to create a bright and airy environment in your home, whilst adding an attractive focal point that is sure to wow your guests.

Not only do they look great, but VELUX skylights are renowned for their superior performances. So your home will benefit from industry-leading levels of thermal insulation, home security and weather-resistance.

Our VELUX Window Options

If you are interested in VELUX windows for your home, check out our 4 top tips for finding out what size you need.

Replacement windows installed in any size from leading double glazing installers

Now you've learnt about the standard UK window sizes, why not find out how to get a price for windows from home?

Window measurements - how to measure them from home?

If you're looking to measure your existing windows from home, check out our expert guide on how to measure windows and doors to get a price from home. It explains everything you need to know about measuring the frame width and height in just a few short steps. Once you've measured up your existing windows, we'll then be able to provide you with a free no-obligation price to replace them.

Looking for a new set of windows for your home? Sheerwater Glass can help. We have over 50 years of installation experience and provide a wide selection of high-quality, made-to-measure uPVC, aluminium and timber windows to homes throughout the South East of England in a range of window measurements.

Give us a call on 01932 344 415 or contact us online and see how we can improve your home today!

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One of our team would be happy to have a chat with you about your requirements, answer any unanswered questions and measure up at a time that suits you to provide you a free, no obligation quote.

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Sheerwater Glass provides window installation and repairs throughout Surrey and the surrounding areas of our Woking showroom. If you’re interested in our services, we encourage you to check if we serve customers in your area by simply typing in your postcode.

If you check and find that we don’t serve customers in your area, in some cases, we may be able to help. Please call us to find out more.

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