Triple Glazing Cost: The Ultimate Windows Guide

woman gazes out of windows with triple glazing


Triple glazing for two-bedroom house costs £2,000-£2,500, on average

A four-bedroom house’s triple glazing will typically cost £6,000-£7,000 

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Is your double glazing just not living up to expectations? This winter, it may be worth adding more than just an extra layer of clothes – instead, try adding an extra layer of insulation.

If your double glazed windows are showing a bit of wear and tear, they could actually be responsible for about 20% of the heat being lost from your home. Although it can be costly, triple glazing could save you from spending your winter shivering the nights away.

Read on to find out how triple glazing can improve your home this winter.

All this talk of money making you feel a little uneasy? Fear not, you can calculate how much double glazed windows will cost you, and compare real quotes with our simple tool.

is triple glazing

In This Guide to Triple Glazed Windows:

Head straight to a specific section by clicking the links below.

What is triple glazing?

If you’re familiar with double glazing, then you’ll be pretty comfortable with its not-so-distant cousin, triple glazing. Triple glazing takes double glazing that extra step further, by simply adding another pane of glass to the window. These three panels of glass act as an extra layer of insulation to your house, keeping you cosy during those bitter winter months.

How does it work?

Triple glazing is a bit like layering up before you brave the winter chill outside – except the insulation isn’t just coming from the extra layers. There is a small gap between each of the three panes of glass, which is either filled with air or an insulating gas, such as argon. Argon is much heavier than air, which means it acts as a stronger barrier against any escaping heat.

This extra third layer also comes with other benefits, such as blocking out any outside noise, providing greater security, and adding value to your home – more on that later. But be careful, you’ll want to double check whether your walls can withstand the weight of triple glazed windows, as the extra layer can sometimes cause structural damage to walls.

is triple glazing worth it

Based on a survey we conducted in May 2018 with 775 homeowners who had installed new double glazed windows in the past two years.

Triple glazing costs

By now, you’re probably thinking what a wonderful, practical product triple glazing is – so what’s the catch?

Well, unfortunately, triple glazed windows typically cost between one fifth and one third more than double glazed windows. An installation of a standard uPVC double glazed window could cost around £465, whereas a triple glazed one would be around £565.

Prices will always vary for windows – it all depends on what type, size, and style of window you’re choosing. Once you’ve settled on all of these deciding factors, it’s time to find a company that will provide you with an accurate quote.

All of these considerations also mean that we can’t give you specific prices, but like a helpful tour guide, we can help you along the way. Check out the table below for an overview of typical triple glazing costs based on house size

Property type
Number of bedrooms
Number of windows
Typical cost

Prices sourced from

As you can see, triple glazing can be quite costly if you have a detached house with lots of windows to replace. If you’re set on this idea, you should know that the more triple glazed windows you install, the cheaper each window will be. In other words, in order to be cost effective, it’s better to have more windows installed, rather than fewer.

Triple Glazing vs double glazing

We’ve already established that triple glazing costs more than standard double glazed windows, but are there any other substantial differences between the two? The short answer, as you may have thought, is yes.

Read on to learn more about the specific features you can expect to see as part of your triple glazed windows.

Thermal performance

The most obvious feature of triple glazing is its ability to keep you that little bit toastier at home. If you’ve started your research on triple glazing, you might be feeling slightly bombarded by ugly acronyms, as well as confusing facts and figures – so we’ll try to keep this simple.

The energy efficiency of a window is measured by its U-value, which refers to how well a window prevents heat from escaping your home. The lower the numerical U-value, the better.

Double glazed windows are typically given a U-value of 1.6, whereas triple glazed windows are rated an impressive 0.8. This means that by simply adding an extra level of insulation, triple glazed windows are proven to provide you with even more warmth throughout the year.

Triple glazing’s superior thermal performance also means it has an energy rating of A++, which is the highest possible rating. To compare, the maximum energy rating that double glazed windows have received is A+, and although this is still impressive, it’s no triple glazing standard.

When it comes to thermal performance, triple glazing wins this round hands down.

Sound insulation

Not only can this extra layer of insulation seal in all of this precious heat, but it can also block out all of that unwanted noise. If you live on a particularly rowdy street and find yourself struggling to sleep through the noise, this investment might be your saviour.

So what’s the science behind this? Well, triple glazing is able to block noise because of the sheer amount of material sound has to travel through. Sound is created through vibration, and as it reaches each pane of glass, the vibration weakens. By the time the sound wave gets through to the final pane of glass (if it gets through at all), it is much quieter and less noticeable.

Home Security

To put it simply: three layers of glass are much harder to break than two. By placing this extra layer of protection on your home, you’re preventing any would-be intruders from helping themselves to your belongings.

Light penetration

Unfortunately, we can’t pick and choose what our triple glazed windows decide to let in and out – while they can block out noise and potential intruders, they also block out light. It’s much harder for light to penetrate that extra level of glass, which might cause your room to feel a little dimmer.

To avoid feeling like you’re hiding away in a cave, we recommend not to install your triple glazed windows on any north-facing walls – this way you still get lots of sunlight brightening up your home, as well as the noise-cancelling, intruder-preventing benefits of triple glazing.

Triple glazing cost vs double glazing cost

By now, you’ve probably got a pretty good overview of the key features of triple glazing, and how it differs from standard double glazing. We can praise triple glazing’s wonderful features until the cows come home, but we know that one thing is at the forefront of everyone’s minds when it comes to making a purchase: the cost.

Although there are numerous different ways that triple glazing trumps double glazing, the expense of triple glazing tends to overshadow the benefits. To give you a rough idea of how much more you can expect to splash out, we’ve created a comparison of prices for different types of window below:

Size (mm)
Double glazing cost
Triple glazing cost
White uPVC
1000 x 500
White uPVC
1000 x 1000
White uPVC
1200 x 1200
Woodgrain uPVC
1000 x 500
Woodgrain uPVC
1000 x 1000
Woodgrain uPVC
1200 x 1200

Prices sourced from Just Value Doors

We calculated these figures based on a basic window frame, as a basis for what you can expect. As you can see, triple glazed windows cost a substantial amount more than double glazing – and, on top of this, are likely to have a longer payback period.

Whether or not this overshadows the other benefits of triple glazing is up to you. If you’d like to find out how much double glazing will cost you, simply fill out this short form, and our qualified installers will be in touch.

Summary of comparison

Whilst both double and triple glazing are excellent ways to insulate your home, triple glazed windows have the overall edge.

Double glazing
Triple glazing
Thermal performance
Sound insulation
Home security
Light penetration

triple glazing


Triple glazing companies

There are two routes you can go down when it comes to choosing a company to install your new window — nationwide or independent companies. Each has its own benefits, but whichever you go with, make sure the company is registered with FENSA (Fenestration Self-Assessment Scheme) or the Glass and Glazing Federation (GGF) — this way you can be sure that the company is legitimate and trustworthy, and will provide you with good results.

Companies can be rated on a range of different things. A common issue with bigger companies is that they sometimes use more of a pressuring tactic with customers, who can often be left feeling obliged to sign a contract.

We carried out a survey of 395 UK homeowners who’ve had triple glazed windows installed in their property in the last two years, with both big companies and local companies, to see what they had to say about their experience:

% of customers who felt pressured to sign a contract
% of customers who rated their installation as good to excellent
Local installer

As you can see, as the company size grows, the percentage of people feeling pressured to sign a contract increases – but so does the quality of installation. Although this might sound intimidating, as you can see from the installation ratings, no matter what type of company you go with, you’re likely to have a good installation experience.

Need a bit more guidance on the most common window installer companies? Take a look at each one’s rating on Trustpilot:

• Everest – 4.3/5
• Safestyle – 4.3/5
• Anglian Home Improvements – 4.1/5
• Zenith Home Improvements – 3/5

Independent companies

If you’re feeling a bit apprehensive about going with a big name brand, an independent company can also be a good option. Take a look at this graph below for a rough idea of the reasons people tend to go with independent window companies:

Data from Which?

Whichever company you go for, you can be assured that you are in safe hands.

So, is triple glazing worth it?

Triple glazing is an effective way to keep your home warmer than ever before – and overall, the benefits of triple glazing will mean that you’re able to save money on bills. However, if you’ve got fairly new double glazed windows, you might want to think about revisiting triple glazing in a few years time, as it’s not likely to save you a huge amount of money.

If your windows are rated A or A+, but you feel like they might need that extra bit of insulation, a more cost efficient idea would be to buy a set of thick curtains, or even install secondary glazing on your existing double glazed windows.

If none of this sounds familiar, and your double glazing is looking a bit worse for wear, then triple glazed windows are definitely worth it. Although expensive, investing in this insulation will bring multiple benefits.

The image below shows a thermographic survey, comparing old double glazing (left) to new triple glazing (right). The red spots on this image show you where the heat is leaving the house, which should tell you everything you need to know about whether triple glazing is really worth it.

Triple Glazing Comparison Against Double Glazing

Pros and cons of triple glazing

pros and cons

What’s next?

Whether you go for double glazing or triple glazing, you can be sure that installing this type of insulation will save you a penny on your bills. Don’t miss out on this window of opportunity.

If you’d like to upgrade to double glazed windows, request a quote, and our qualified installers will be in touch. It’s time to provide your home with an extra layer of warmth, protection, and soundproofing.

Beth Howell Writer

Beth is The Eco Experts’ newbie. She’s keen to use her writing skills, and passion for green living, to help the environment. Whether you’re after a new boiler, or just interested in how solar panels can improve your home, she’s got your back.