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Last updated: 21 November 2023

uPVC Windows Sizes: Standard Widths & Heights

standard uk window sizes

Are you looking to upgrade your home with uPVC windows but don’t know where to start or how to proceed? One crucial factor to consider before shopping around is the uPVC window sizes. If you skip this step, you can still get beautiful and energy-efficient windows, but they may not fit well within your walls.

Standard uPVC window sizes vary depending on the style, which can make the decision-making process overwhelming. However, understanding the different uPVC window sizes can ensure you choose the perfect fit for your home.

uPVC window sizes in the UK typically range from 488mm to 1,770mm in width and 488mm to 1,500mm in height, but this varies by style. For example, a casement window typically ranges from 635mm to 750mm in width and 900mm to 1,500mm in height, while a sash window ranges from 914mm to 2,134mm in width and 609mm to 1,524mm in height.

Too complicated? It doesn’t need to be. If you are ready to upgrade your home with modern uPVC windows, the easiest and smartest way is using GreenMatch’s free quotes service. Our team of experts on domestic energy solutions will:

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Standard uPVC window sizes

uPVC windows are available in a range of standard sizes to cater to different needs. According to industry standards, a large uPVC window design can have a size of up to 2.65 metres squared. Some manufacturers offer custom-made, extra-large uPVC windows that can be even bigger, with sizes up to 4 metres squared or more. 

On the other hand, small UPVC windows are also available to suit the specific requirements of a given space. In any case, the different window styles in uPVC are probably the most important factor determining standard UK uPVC window sizes. 

For example, considering the sash style, a 1200 x 1200 uPVC window is within the standard uPVC window sizes in the UK. The same measurements, nevertheless, would make top-hung windows fall outside the category of standard-size uPVC windows.

Always keep in mind that every windows manufacturer has their own set limits in terms of the minimum and maximum dimensions they will allow.

There are several factors that can affect the maximum width and height one window can reach. This includes:

  • Glazing and its weight
  • Inward or outward opening
  • Attached hardware
  • Weather and location the window is exposed to. 

Below, you can find a table summarising uPVC windows standard sizes in the UK. Right after, the following sections will delve into what uPVC window sizes are standard for different window styles.

uPVC Standard Window Sizes (Widths & Heights)
Standard uPVC window widthsStandard uPVC window heights
488mm (19 inches)488mm (18 inches)
630mm (25 inches)600mm (24 inches)
915mm (36 inches)1,050mm (42 inches)
1,200mm (48 inches)1,200mm (48 inches)
1,770mm (70 inches)1,350mm (54 inches)
1,500mm (60 inches)

Sash windows

average window sizes - sash

Sash windows are windows that consist of two vertically sliding panels, also known as sashes. They are typically made of multiple small glass panes held together. In addition to uPVC, other common options include timber windows and aluminium windows.

Sash windows are a popular choice for traditional or period properties, and are known for their elegant design and ability to provide excellent ventilation. They typically range in size from 914mm to 2,134mm in width and 609mm to 1,524mm in height, making them a versatile option for different home styles and sizes.

Standard Sash Window Sizes (Widths & Heights)
Standard Window WidthsStandard Window Heights

Casement windows

average window sizes - casement

Casement windows are hinged on one side and open outward, like a door, using a crank or lever mechanism to operate. They are typically made up of a single pane of glass, although they can also feature multiple panes divided by muntins.

Casement windows are popular for modern homes and buildings, as they provide a sleek and streamlined appearance. They generally range from 635mm to 736mm in width and 890mm to 1,500mm in height, although custom sizes can be manufactured to fit specific requirements.

Standard Casement Window Sizes (Widths & Heights)
Standard Window WidthsStandard Window Heights

Tilt and turn windows

average window sizes - tilt and turn

Tilt and turn windows are a versatile type of window that can open in two ways. They can either be tilted inward from the top for ventilation or turned inward from the side for easy cleaning and maintenance.

They are typically made up of one or more panes of glass and are popular in modern homes and buildings due to their functionality and contemporary appearance. Tilt and turn windows generally range from 500mm to 1,300mm in width and 600mm to 1,900mm in height. Custom sizes are also available.

Standard Tilt and Turn Window Sizes (Widths & Heights)
TypeStandard Window WidthsStandard Window Heights
Single Tilt and Turn500mm (min)600mm (min)
1,300mm (max)1,900mm (max)
Double Tilt and Turn1,200mm (min)600 (min)
2,400mm (max)1,700mm (max)
Triple Tilt and Turn (2 Outer Opening Panes)1,600mm (min)600 (min)
3,000mm (max)1,900mm (max)

Bay windows

average window sizes - bay

Bay windows protrude outward from the wall of a building. They are typically made up of three or more windows angled to create a bay or alcove inside the building. Bay windows provide a range of benefits, such as increasing natural light, providing a wider view of the outside, and creating additional space inside the room.

Bay windows come in a variety of sizes, with widths ranging from 101.6cm to 320cm and heights ranging from 91.44cm to 198.12cm. The size of a bay window can vary depending on the building’s architecture and the room’s intended use.

Standard Bay Window Sizes (Widths & Heights)
Standard Window WidthsStandard Window Heights
101.6cm (minimum width)91.44cm (minimum width)
320cm (maximum width)198.12cm (maximum width)

Bow windows

average window sizes - bow

Bow windows are curved windows that protrude from the wall of a building, creating an arc or angle. They are often used as a design feature to add more natural light and space to a room. Bow windows consist of three to six individual windows that are connected together, creating a more rounded appearance than bay windows.

Standard bow windows are usually 2,400mm to 3,000mm in width and 1,200mm to 1,500mm in height, but they can be customised to fit specific requirements. Bow windows are commonly used in living rooms, dining rooms, and bedrooms to add a unique touch to the space.

Standard Bow Window Sizes (Widths & Heights)
Standard Window WidthsStandard Window Heights

Be it sash, casement, tilt and turn, or any other style, getting windows of the right size is essential to ensure functionality and even improve energy efficiency. If you are unsure what uPVC window size you need, we can put you in touch with up to 4 top-rated suppliers in your area for expert advice. 

At GreenMatch, we ensure the local companies we match you with meet the highest quality standards. Our service is 100% free, and you are not obliged to accept any quote you receive. To start, just click on the button below.

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How to measure your existing windows

Measuring uPVC windows accurately is essential to ensure you get the right size and fit for your replacement windows. It can even determine if the window will achieve your desired energy efficiency standards. Here is a step-by-step guide on how to measure windows correctly:

how to measure windows
  1. Gather your tools: You will need a tape measure, a pen, and paper to write down the window measurements.
  2. Determine the type of window: Different window styles require different measuring techniques. Identify whether your window is a casement, sliding sash, tilt and turn, or any other style.
  3. Measure the width: Measure the width of your window frames from one side to the other. Take the measurement at the widest point, including any trim or frame. Measure the width at the top, middle, and bottom points and record the smallest width measurements.
  4. Measure the height: Measure the window frame size from top to bottom, including any trim or frame. Take the measurement at three different points – left, centre, and right – and record the smallest measurement.
  5. Measure the depth: Measure the depth of the window frame from the inside of the frame to the outside. This measurement is essential if you’re planning to replace the entire window.
  6. Note any obstructions: Check for obstacles that may hinder the window’s operation or affect the size. Examples include locks, handles, hinges, or any other protrusions.
  7. Check for squareness: Determine if the window is square by measuring from corner to corner diagonally. If the measurements are not equal, the window is not square.
  8. Take a photo: If possible, take a picture of the window, including any obstructions or features that may affect the size or shape of the window.
  9. Double-check your measurements: Before ordering your new windows, double-check your measurements to ensure they are accurate.

Get the best deal on replacement windows

Without a doubt, comparing quotes is one of the best ways to get the best deal on replacement windows. This is why:

  • It helps you find the best price: By comparing quotes from different suppliers, you can easily identify which offers the most competitive price for your desired uPVC window style.
  • It allows you to evaluate the specifications and quality of the product: The cheapest option may not always be the best. By comparing quotes, you can check uPVC window sizes and prices and also their quality. This includes the windows’ energy efficiency, durability, and overall performance.
  • It gives you leverage for negotiation: Having multiple quotes at hand gives you an advantage when negotiating with suppliers. You can use these quotes to ask for a better deal. Many window suppliers and double-glazing companies offer price matching for quotes from other providers or even triple-glazing upgrades.

However, manually searching for local window companies and requesting quotes one by one can be tedious and time-consuming. This is where GreenMatch can help you. Our free quotes service is designed to provide assistance in finding top installers in your area, ensuring you get the best deal. Check out how it works:

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Luis Antonio Gómez Pérez

Luis Antonio is a seasoned Content Writer with international journalism experience. His writing style, enriched by a Master’s in Journalism, contributes informative content to GreenMatch on topics including low-carbon heating systems.

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