The Independent’s journalism is supported by our readers. When you purchase through links on our site, we may earn commission. Why trust us?
Bay windows are an elegant addition to your property. They enhance its character by bringing additional natural light into its rooms and creating extra floorspace.
This guide tells you everything you need to know about bay window prices and the impact that your choice of frame material and design style can have on them. It also offers tips on how to choose the bay window deal that’s right for you.
Complete our short form to request windows quotes for your home
Get free, no obligation quotes from up to 4 local windows installers
Compare quotes and pick the option that best suits your needs
Bay windows are one of the most expensive styles on the market, with installation costs ranging from £1,700 to £8,400.
Bay windows project outwards from a property. Typically, they are composed of a prominent central window with two smaller, angled windows on either side, resulting in a rectangular bay shape. Larger bays can be designed by incorporating additional window panels.
Each panel of a bay window costs as much as a similarly sized casement window, with an additional £75 per panel for connecting struts.
Several key factors affect the prices of bay windows:
| Bay window frame material | 1,016mm x 914mm | 3,200mm x 1,980mm |
|---|---|---|
| uPVC | £1,700 | £2,800 |
| Aluminium | £3,400 | £5,600 |
| Timber | £5,100 | £8,400 |
Durability and low maintenance make uPVC a popular frame material for bay windows. Though their prices can vary depending on their finish, uPVC frames are generally considered cost-effective.
Aluminium windows have a sleek, modern look. They are known for their superior durability, slim profile and long lifespan. This type is usually more expensive than a uPVC bay window.
Timber frames have a classic, traditional aesthetic. They can be constructed from softwoods such as pine and hardwoods such as oak and beech. Timber bay windows are often the most expensive option due to the material costs and the required craftsmanship. Over time, they need more maintenance than other types of bay window frames.
| Bay window shape | Average price |
|---|---|
| Canted | £1,190-£2,700 |
| Box | £1,690-£3,200 |
| Oriel | £1,690-£3,200 |
| Circle | £2,190-£4,700 |
A bay window’s shape can significantly impact its cost. There are several shapes to choose from, depending on your architectural preferences and whether you’re considering ground-floor or first-floor windows.
Traditional bay windows, which are also known as canted bay windows, consist of three or more window panels. A canted bay has a flat front and sides that are usually set at 30- or 45-degree angles. Canted bays offer broad views of the outdoors and allow lots of natural light into interior spaces. Canted bays are suitable only for ground-floor rooms.
On average, a canted bay window’s cost ranges from £1,190 to £2,700.
Box bay windows are also known as square bay windows. A box bay is structurally similar to a canted bay, except that the box bay’s flanking windows meet its front panel at 90-degree angles to create a squared-off shape.
On average, a box bay window’s cost ranges from £1,690 to £3,200.
Oriel bay windows, which are the earliest bay design, can be seen on English Renaissance mansions. This type of window remains popular today. Oriel bays can be installed on properties’ upper floors because they have decorative brackets or corbels made from wood, stone or masonry that serve as structural supports.
On average, an oriel bay window’s cost ranges from £1,690 to £3,200.
Circle bay windows feature semicircular designs and are especially large. This type of window, which is typically installed on ground floors, lets in abundant light and is architecturally detailed.
On average, a circle bay window’s cost ranges from £2,190 to £4,700. But larger, more complicated designs may be more expensive.
| Bay window design | Average price |
|---|---|
| Three-panel casement | £1,700 |
| Three-panel tilt and turn | £2,300 |
| Three-panel sash | £3,000 |
Bay windows consist of joined panels that are available in various designs with different price points.
Casement windows are typically the least expensive design. Their hinge arrangements and opening mechanisms make them suitable for use in any type of bay window shape.
Tilt and turn windows can be operated in two different ways. They can swing open like casement windows, or they can be tilted from the bottom, which makes the top of the window angle into the room. The casement design is a more popular option for bay windows than the tilt and turn design.
Bay windows can incorporate a sash design, in which some or all the window sections have parts that slide up and down to open them. A three-paned sash bay window typically consists of a fixed central window with sash windows on either side of it.
| Glazing type | Average cost of a uPVC bay window |
|---|---|
| Double glazing | £1,250-£,1,650 |
| Triple glazing | £2,000-£2,300 |
The type of glazing you select for your bay windows significantly impacts their total cost.
Double glazing is a common choice for bay windows. This type of glazing is known for its superior insulation and energy-saving properties. Factors that affect the price of a double-glazed bay window include the quality of the glass and the dimensions of the window.
The average cost of a double-glazed uPVC bay window is between £1,250 and £,1,650. Although the initial expense can be substantial, this type of window is cost-effective over time.
Triple glazing, which offers enhanced insulation, is a pricier option than double glazing. The average cost of a triple-glazed uPVC bay window is between £2,000 and £2,300.
Secondary glazing involves the addition of a layer of glass on the room side of an existing bay window. Secondary glazing boosts insulation and reduces external noise. Applying secondary glazing to windows is generally cheaper than replacing them with double-glazed or triple-glazed windows.
When comparing costs and quotes for bay windows, use a systematic approach to make sure you get the best value for your money.
Bay windows are costlier than many other types of windows. That’s because bay windows have more complex designs than flat windows and require additional materials and a more skilled approach to their installation.
Bay windows made from uPVC are a popular choice with consumers primarily because they are durable, low-maintenance, energy-efficient and cost-effective.
Frames constructed from uPVC resist weathering and retain their appearance over time without the need for frequent painting or sealing. They offer excellent insulation, which helps to reduce heating costs, and are available in many different colours and finishes. Also, uPVC bay windows are more affordable than aluminium or timber ones.
A bay window is generally less expensive than a bow window, with the cost depending on several factors. Both designs are similar in their architectural appearance and their ability to add space and light to property interiors. But bow windows, which have a curved structure, can be more expensive than bay windows, which have an angular design unless they are circle bay windows.
Ultimately, project details such as design complexity, material choices, window size and installation requirements determine the cost differences between bay windows and bow windows.
