Double Glazed Windows Cost

Wondering how much uPVC windows cost to fit?

The average cost of fitting new double glazed uPVC windows is £4,500. The exact price depends on the number of windows, the type of frame you choose, your location, and whether you need professional installation or just supply.

This UK guide will help you narrow down how much double glazed windows are likely to cost for your home, how long they take to fit, and what the job involves.

It’s best to get quotes early on—even if you are just exploring your options. It’s the first step to see what’s realistic for your budget.

With MyJobQuote, you can quickly get quotes from window fitters near you. It’s free and with no obligation.

See our full double glazed window cost guide below.

How Much is Double Glazing?

The cost of double-glazed windows varies depending on the size, style, frame material, and number of windows you need. On average, you can expect to pay between £3,000 and £6,000 for a full installation of standard uPVC double-glazed windows. Higher-end options, such as custom shapes, premium materials, or energy-efficient glass, can increase the price.

Use our calculator above for a personalised estimate based on your home and requirements, or see the table below for a breakdown of typical prices for different types of double-glazed windows to help you plan your budget.

Double Glazed Windows Prices

For a different number of windows, you can estimate from these prices. For example, the cost to fit 7 windows would likely fall between £2,500 and £3,000, while 9 windows would be between £3,000 and £3,600.

When looking at the price of double glazing, it's important to factor in the type and material of the frames, the number of windows, and the installation process. Comparing prices for different materials like steel, timber, and aluminium can help you find the best deal.

If you’re still deciding between uPVC, aluminium, or timber frames, see our full guide to new window costs for a detailed comparison of materials, pros and cons, and long-term value.

Costs by Window Size and Type

Both the size and type of window will affect the overall price. Larger windows require more materials, glazing, and installation time. The style of frame can also make a big difference. Casement windows are simpler and usually installed in larger numbers, while bay or tilt & turn windows are more complex and often used in smaller quantities per home.

The table below shows average supply and installation costs for common window sizes and types, based on standard uPVC double glazing.

Labour Costs for Fitting Double Glazed uPVC Windows

As a general rule, you can expect labour to make up £300 to £750 of the total cost for a full house installation, as shown in our table.

If you are hiring a fitter by the day, a typical day rate for a FENSA-registered window fitter is between £200 and £300. A single, straightforward window replacement may only take 2-3 hours and cost £75 to £150 in labour.

Double Glazing Cost Calculator (Including Installation)

Replacing Your Doors

If you’re replacing your windows, it often makes sense to update your external doors at the same time. This helps maintain a consistent look across your home, improves energy efficiency, and can even save you money on labour since both jobs can be completed together.

For a standard uPVC front or back door, you can expect to pay £700 to £1,200 including supply and installation. The final price will depend on the door’s size, design, and security rating.

As a rough guide, if you’re replacing eight windows and two doors, your total might be around £3,000 to £3,600 for the windows plus £1,400 to £2,400 for the doors.

Upgrading to sliding patio doors, French doors, or composite front doors will increase the cost. These typically start from around £1,200 to £2,000 depending on size, glazing type, and finish.

Additional Costs When Fitting Double Glazing

When budgeting for new uPVC double‑glazed windows, the quoted cost often covers the basic frame, glazing and standard installation. However, several extra costs can appear depending on the specifics of your property and requirements. Here are the most common add‑ons:

• Scaffolding or access equipment — If your windows are on an upper floor, in a difficult position or your installer needs additional safety equipment, you may need to cover the cost of scaffolding or access towers.
• Replacement of sills, reveals or structural repairs — If your current sill or frame is damaged or rotten, or if the opening needs adjustment, then works such as replacing sills or repairing masonry/plaster may add cost.
• Making good finishes & décor touches — After installation you may need to repaint or redecorate internal window reveals, external trim or other areas disturbed during fitting.
• Waste disposal — Check whether your installer takes away the old frames/glass and disposes of it responsibly. If not, skip hire or separate waste‑removal costs may apply.
• Upgraded glazing or hardware — Standard double glazing is usually included, but upgrades (acoustic glass, laminated or toughened safety glass, solar control glazing) or premium handles and locks will increase the price.

By allowing for these possibilities you’ll avoid budget surprises later in the project.

Factors That Affect the Cost of Double‑Glazed Windows

The final quote you receive will depend on a combination of factors. Knowing these will help you compare quotes more intelligently and plan your budget accordingly.

• Frame material and finish — Even with uPVC, differences such as plain white vs coloured or wood‑effect finishes can affect cost.
• Window size and style — Larger windows or complex styles (bay windows, sash windows, tilt‑and‑turn etc) require more material and labour and so cost more.
• Glazing specification — Standard double glazing is least expensive. If you opt for triple glazing, acoustic glass or specialist coatings you’ll pay more.
• Number of windows and bulk effect — Installing many windows at once may lower the average cost per window due to efficiencies; a one‑off single window will often be a higher “per‑unit” cost.
• Location and accessibility — Installations in London or the South‐East often cost more than in other UK regions. If access is difficult or scaffolding is required your cost will increase.
• Labour vs supply only — Some quotes cover supply only (you arrange fitting) while others are full supply and fit. The difference in labour cost is significant.
• Extra features and regulatory compliance — Enhanced security hardware, trickle vents, building‑regulations compliance (especially for listed or conservation properties) can add to cost.

Understanding how each of these pulls on your total cost helps when you get quotes and decide what trade‑offs you might make.

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What is Double Glazing?

Double glazing is a type of window insulation that involves fitting two glass panes separated by a small gap, typically filled with air or gas. This gap acts as a barrier, reducing heat transfer between the inside and outside of a building and minimising noise pollution. Double glazing is an effective way to improve energy efficiency, reduce energy bills, and enhance the overall comfort of a home.

What Are uPVC Windows?

uPVC stands for unplasticised polyvinyl chloride, a durable and low-maintenance material used for window frames. Unlike traditional wooden frames, uPVC does not rot, warp, or require regular painting. Most modern double-glazed windows use uPVC frames because they are energy-efficient, long-lasting, and cost-effective.

Types of Double Glazed Windows

There are several types of double glazed windows available, each with its unique characteristics and benefits. Some of the most common types include:

Casement Windows

These windows open on a side hinge and are known for their energy efficiency and durability. Casement windows are a popular choice for many homeowners due to their ease of use and ability to provide excellent ventilation.

Sash Windows

These windows have two framed panels that slide up and down over each other, providing excellent ventilation and aesthetic appeal. Sash windows are often found in older homes and are valued for their classic look.

Sliding Sash Windows

These windows have a horizontal sliding sash and are known for their ease of use and energy efficiency. Sliding sash windows are a great option for spaces where you want to maximise the view and natural light.

Tilt and Turn Windows

These windows can be securely left open for ventilation by tilting them inwards while remaining fully locked. Tilt and turn windows offer versatility and are ideal for modern homes.

Bay Windows

These windows extend out from the room and require three windows instead of one, providing a unique architectural feature and increased natural light. Bay windows can make a room feel larger and more inviting.

Things to Consider

Before committing to uPVC, it’s important to weigh its benefits and drawbacks compared to other frame materials like wood or aluminium. Here’s a concise guide to help you decide:

Advantages

• High Weather Resistance — uPVC is highly resistant to moisture, corrosion, and extreme temperatures, making it ideal for the UK climate.
• Low Maintenance — Unlike wood, uPVC won’t warp or rot. Frames require very little upkeep, aside from occasional cleaning with a damp cloth.
• Long Lifespan — A typical uPVC window lasts 25–35 years or more with minimal degradation, remaining structurally sound throughout its life.
• Cost-Effective — Standard white uPVC frames are the cheapest option for double glazing replacements, making them an accessible choice for most homeowners.
• Strong Thermal Performance — uPVC contributes to high Window Energy Ratings (WER) and can help reduce heating bills over time.
• Variety of Glass and Styles — uPVC frames can accommodate many glass types such as plain, leaded, Georgian bar, tinted, double glazing, and triple glazing. They are also compatible with a wide range of window styles, including casement, sash, tilt & turn, bay, bow, and fixed windows.

Disadvantages

• Appearance — Some homeowners prefer the traditional look of wood which costs more; uPVC can appear plain or less visually appealing in certain homes.
• Environmental Impact — The manufacturing process is petroleum-based and energy-intensive, though the frames themselves can be recycled at the end of their lifespan.
• Colour Options — While standard white is inexpensive, choosing alternative colours can significantly increase the cost of replacement windows.
• Discolouration Risk — Lower-quality or older uPVC frames may yellow or fade slightly over time, although modern materials are more resistant to this issue.

DIY Double Glazed Window Installation

To fit new double glazed windows and replacement double glazing doors in the UK, FENSA registration is required.

However, the basic process of fitting windows is reasonably straightforward for a decent DIY enthusiast. Double-glazing comprises the frame, the sill and the glazing unit. When you order uPVC windows from the manufacturer, they usually arrive separately in parts, with the beads in the frame.

When you remove your old windows, it is critical that you do so carefully, as the more of a mess you make of the walls and plaster, the more work you will have later making it good! Be especially careful with damp proof courses and ensure that they have not been pulled out with the old window frame.

If they have been moved or damaged accidentally, you need to replace or refit them properly. Then simply fit the new windows in place using bolts and then seal carefully around the edges of the frames.

Does Double Glazing Add Value to a House?

Yes, double glazing can add significant value to a house. According to various studies, installing double glazing can increase the value of a property by up to 10%. This is because double glazing provides numerous benefits, including:

• Improved energy efficiency — Double glazing can reduce energy bills and minimise heat loss, making a home more attractive to potential buyers. Energy-efficient homes are increasingly in demand as people look to reduce their carbon footprint and save on utility costs.
• Enhanced aesthetic appeal — Double glazing can improve the overall appearance of a home, making it more desirable to potential buyers. Modern double glazed windows come in various styles and finishes, allowing homeowners to choose options that complement their home’s design.
• Increased security — Double glazing provides an additional layer of security, making a home more attractive to potential buyers. The robust construction of double glazed windows makes them harder to break, offering homeowners peace of mind.
• Reduced noise pollution — Double glazing can minimise noise pollution, making a home more comfortable and desirable to potential buyers. This is particularly beneficial for homes located in busy or noisy areas.

Overall, double glazing is a valuable investment that can add significant value to a house, making it more attractive to potential buyers and increasing its resale value.

Checklist: Hiring a uPVC/Double Glazing Fitter

Ready to hire a local specialist for your uPVC or double glazing installation? Here's what you should keep in mind to ensure a professional job:

• Are they qualified? Check that your fitter has recognised qualifications or is registered with a professional body such as FENSA, Certass, or BM TRADA. This ensures the installer meets current building regulations for thermal efficiency and safety.
• Do they have insurance? Make sure your fitter holds public liability insurance (typically £1 million or more) to cover accidental damage or injury during the job. Ask to see proof before work begins.
• Can they provide references? Ask for examples of previous installations, especially for similar property types or uPVC window styles. Reputable fitters will be happy to share photos or customer feedback.
• Have they provided a written quote? Always request a detailed written quote outlining materials, labour, VAT, and any optional extras like coloured frames or upgraded glazing. Avoid paying large deposits upfront.
• Are the product specifications clear? Check that your quote includes details of the exact products being fitted, such as frame material, glazing type, energy rating, and locking systems. This ensures you’re comparing like-for-like between quotes.
• Will they register your installation? FENSA and Certass-registered installers can self-certify your new windows and issue a certificate to confirm compliance with building regulations. If your fitter isn’t registered, you’ll need to arrange inspection through your local council instead.
• Do they offer a warranty? Look for companies that include a written guarantee on both the frames and glazing, ideally backed by an insurance policy. Most reputable installers offer at least a 10-year warranty.
• Are payment terms clear? Confirm when and how payments are due. Avoid paying the full amount upfront — a small deposit (typically 10% to 25%) is standard, with the balance due after completion and satisfaction checks.
• Are they clear about timescales? Confirm how long the installation will take, including lead times for manufacturing the windows. A typical replacement window job takes one to two days for a full house.

Following these steps will help you choose a qualified, fully insured window fitter who offers value, compliance, and peace of mind.

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