New Window Prices: How Much Do Replacement Windows Cost?

Main Factors that Determine the Cost of Windows

You can find a wide selection of windows in the market, with different designs and materials. In general, the cost of a window depends on the following factors:

Window Features	Main Options	Cost Comparison
Frame Material	uPVC / Aluminium / Timber	uPVC windows are the most affordable. Aluminium windows have an intermediate cost. Timber windows are the most expensive.
Window Type	Casement / Sash / Tilt & turn / Bay / Bow	Casement windows are the most affordable, followed by tilt & turn windows. Sash windows have an intermediate cost. Bay and bow windows are the most expensive.
Glass Type	Double glazing / Triple glazing	Triple-glazed windows are more expensive, but they also improve energy efficiency.

*NOTE: Double glazing (or better) is mandatory for UK homes built after 2002, but you can still find single-glazed windows in older properties. Upgrading single-glazed windows is not required by law, but strongly recommended to improve energy efficiency. See more about double glazing costs.

Window prices can also vary depending on the installation company and the complexity of the project. For example, windows located on a second floor have higher installation costs, since the process requires scaffolding and additional safety measures. Window replacements have slightly higher costs than window installations in new homes, since additional labour is required to remove the existing units. To ensure professional workmanship, you should look for a FENSA-approved window installer.

Regardless of the type of windows used in your home, we recommend getting multiple quotes to ensure the best possible price. The Energy Savings Trust also recommends looking for high-efficiency windows: a typical home with gas heating can save £155 per year with A rated double glazing, and £170 per year with A+++ rated double glazing.

Having single-glazed windows is not illegal in the UK, but you cannot install them on a new property.

• Double-glazed windows are now used in around 60% of UK homes, giving their energy efficiency and noise reduction benefits.
• They also make your home more comfortable during winter by reducing heat loss.

In the following sections, we will review the typical prices of the five main window types used in the UK: casement, sash, tilt & turn, bay and bow. Our comparison is based on the estimated window prices published by the Federation of Master Builders (FMB).

Cost of Casement Windows

Casement windows have a simple design and a lower price range than other types. These windows have a hinged side and they open just like a door.

Casement Window Frame Material	Estimated Price per Window
uPVC	£372 – £961
Aluminium	£744 – £1,147
Timber	£1,147 – £1,829
Composite	£2,046 – £3,596

The main disadvantage of casement windows is their outdoor space requirements. Since these windows open outwards, they are not suitable for locations with limited space or obstructions.

Cost of Sash Windows

Sash windows open by sliding vertically or horizontally along their frame. This design makes them ideal for properties with limited outdoor space. They are also suitable for areas with plenty of pedestrian traffic, where casement windows can cause an accident.

Sash Window Frame Material	Estimated Price per Window
uPVC	£719 – £1,159
Aluminium	£1,178 – £1,674
Timber	£1,612 – £2,356

Sash windows require more maintenance than casement windows, since they rely on a sliding mechanism that is exposed to constant friction.

Cost of Tilt & Turn Windows

Tilt & turn windows have two opening methods, as you might guess from their name. They can open outward like a casement window, but they can also tilt inward. The FMB provides estimated prices for uPVC tilt & turn windows of different sizes:

• 800mm x 800mm = £600
• 1,000mm x 1,000mm = £695
• 1,200mm x 1,200mm = £750

The main advantage of tilt & turn windows is their versatility. If they cannot swing outwards due to a temporary obstacle or a gathering of people, you can still ventilate your home by tilting them inwards. These windows can also be tilted while their turning mechanism remains locked, which means you can have natural ventilation without compromising security.

Cost of Bay Windows

In simple words, a bay window is an array of three or more individual windows joined at an angle. This window arrangement gets its name because it creates a “bay” that projects outward from the wall. As you might guess, bay windows are more expensive than individual windows.

Here are the typical costs of bay windows as reported by the FMB, considering three frame materials and two window sizes.

Bay Window Frame Material	1,016 mm x 914 mm	3,200 mm x 1,980 mm
uPVC	£1,700	£2,800
Aluminium	£3,400	£5,600
Timber	£5,100	£8,400

The FMB also provides estimated price ranges for uPVC bay windows based on their number of sections:

• 3-section bay window = £1,364 – £1,674
• 4-section bay window = £1,922 – £2,170
• 5-section bay window = £2,542 – £2,790

Bay windows also offer design flexibility with respect to the individual windows that are joined together. For example, you can use three casement windows or three sash windows.

Cost of Bow Windows

Bow windows are also composed of several units, similar to bay windows. The difference is that bay windows are arranged in sharp angles, while bow windows have a semicircular arrangement. In this case, the individual units that can be either casement or sash windows.

Here are the typical costs of bow windows, considering two sizes and three material options:

Bay Window Frame Material	1,016 mm x 914 mm	3,200 mm x 1,980 mm
uPVC	£1,700	£2,800
Aluminium	£3,400	£5,600
Timber	£5,100	£8,400

The FMB also provides estimated costs of uPVC bow windows, by number of sections:

• 3-section bow window = £1,426 – £1,674
• 4-section bow window = £1,922 – £2,170
• 5-section bow window = £2,480 – £2,728

Understanding Window Frame Materials

There is a common misconception that uPVC frames are inferior due to their price, but this is only true if you purchase low-quality products. uPVC windows offer thermal efficiency and durability while having simple maintenance needs. You may have heard that uPVC frames deform over time, but this only happens if the material is of lesser quality.

Aluminium offers increased durability if you are willing to pay the extra price. This frame material has simple maintenance needs and can be found in several colours. Aluminium windows used to have a low energy efficiency, since metals tend to have poor insulation properties. However, modern units with thermal breaks can match the efficiency of uPVC windows.

Timber is the most expensive window frame material, having both a higher price and a higher maintenance cost. However, timber is widely regarded as a luxury material, adding aesthetic value to your property. For this reason, homes with timber windows tend to sell for higher prices in the real estate market.

Frequently Asked Questions (FAQ) About UK Window Costs