How Long Does Double Glazing Last?

Double glazing can be a magical solution to many problems, as it provides efficient insulation against extreme temperatures and loud noise. 

How long does double glazing last, though?

Generally, double-glazing units in windows, doors, and even conservatories can last between 20 and 35 years. However, with the proper care and maintenance, double glazing may last longer. 

Read on for more information about the general lifespan of double glazing, the factors affecting it, and how to tell if your double glazing needs replacing.

Factors Affecting the Lifespan of Double Glazing

Here are the main factors that affect the longevity of double glazing:


The location of your house is one of the most important determinant factors. 

For starters, a double-glazing unit near the ocean will generally have a shorter lifespan than another in the countryside. That’s due to the quality of the air in those areas.

The acidity of the air near oceans can decrease the lifespan of double-glazing units. Unfortunately, there’s no way to avoid this despite the recent technological advancements.


In addition, the location of the unit itself makes a difference. 

For instance, a north-facing window or door can last longer than a south-facing one. The temperature and sun exposure plays their part in this situation.

In other words, two double-glazed windows in the same house can have different lifespans depending on their exposure to the sun, rain, and heat.

Quality of Manufacture and Installation

The quality of the material and the proficiency of the installer can have a say in a double-glazed window’s lifespan as well. 

A high-quality double-glazing unit that is properly installed by a qualified professional can generally last longer. That’s why you should rely on the pros, like us here at Homeshield!

Fortunately, you can install double-glazing units on different frame materials, such as uPVC, aluminium, or timber. However, you should make the right investment in quality materials and craftsmanship.

How to If Tell Your Double Glazing Needs A Replacement

Your double-glazing unit can give you several indications that it needs replacing. You should replace your double-glazing units in the following scenarios:


If you feel draught or strange coldness around your unit’s frame, it most probably needs replacing.

Double glazing comes with Argon gas between the panes, and draught means that this gas has gone to waste.

Condensation or White Dust

Typically, there’s Silica gel in the unit’s spacer bar to absorb moisture, preventing fog and condensation between panes.

When the unit fails, the silica gel breaks, which may lead to the appearance of white dust. In addition, it leads the unit to develop moisture due to thermal pumping. 

If you see condensation or white dust between the panes, your double glazing requires replacing. 

Fading Furniture

Double glazing units offer UV protection, which protects your furniture and carpets from losing colour. However, when your unit fails, your home becomes exposed to harmful sun rays, which causes the fading of furniture.

You may not spot this problem quickly since it takes a long time for your furniture and carpet to lose colour. Therefore, you should keep an eye out for the tiniest change.

Physical Damage

It’s normal to notice some wear and tear after some time. However, you should be alert if you see large cracks or rotten portions.

That can be an alarming indication that you should replace your unit as soon as possible. Otherwise, you risk the formation of mould.

Increased Energy Bills

If your energy bill increases suddenly, the double-glazed windows or doors have most probably failed to prevent the outside heat from seeping in. 

That’s a clear sign that your double-glazing unit has lost its insulating abilities and needs replacing. 

Inability to Open and Shut

Sometimes, your double-glazing unit can get stiff or even shut on its own. Most probably, the insulation has failed, and your unit requires a replacement. That can be due to the moisture that has built up inside the unit as it stops functioning.

In fact, this failure can happen when you use cheap installation materials. That’s why you should invest in good quality material for the frames of your double-glazed windows or doors to avoid such problems.

Inefficient Insulation

One of the main functions of double glazing is noise and cold insulation. Thus, hearing outside noise or getting cold drafts through your double-glazing unit is a tell-tale sign that it’s time for a replacement.

In this case, the Argon gas has escaped from your sealed unit, leaving the panes without proper insulation.

The Advantages and Disadvantages of Double Glazing Units

Before installing double-glazing windows, doors, orangeries, or conservatives, you should consider their advantages and disadvantages.

The Advantages of Double Glazing Units

Here are some of the main advantages of installing double-glazing units:

Saving on Energy Bills

Most people go for double glazing primarily for its insulation capabilities. It protects your home from extreme heat or cold. 

That makes your house cooler in the summer and hotter in the winter. Therefore, you won’t consume much energy on air conditioning or heating your home, which reduces energy bills.

Soundproofing Your Home

Double glazing doesn’t only insulate your house against temperature but also noise. You’ll notice how quieter your home gets after installation.

That quality makes double glazing an ideal option for those who live near airports or busy roads in the UK.

Increasing Your Security

Double-glazing units are tough and thick. They’re not easy to break, which makes your home safer and more secure.

That can discourage burglars from trying to break into your house. Thus, double glazing is an ideal option for those who live in far-away areas or dangerous neighbourhoods.

Providing UV Protection

Ultraviolet rays can be harmful to the interior of your house. At least, it can cause the fading of walls, furniture, and carpets. 

Double glazing offers you UV protection, which keeps your interior in good quality.

The Disadvantages of Double Glazing Units

On the flip side, there are some disadvantages to installing double-glazing units, including:

High Initial Costs

Double glazing is more expensive than regular glass units. That’s mainly because more material is used in their construction.

The good news is that if you invest in good quality material and craftsmanship, you can save much later on energy bills.

No Repairs

Unfortunately, if your double-glazing unit fails, you have to replace it. There’s no way to repair a sealed unit.

That’s why it’s important to hire a skilled professional for the job. Otherwise, you may have to pay more for a replacement.

Causes of Double Glazing Failure

On top of the factors determining the longevity of double glazing, several reasons may cause the failure of double-glazing units. 

Try to avoid these causes to have your double-glazing unit functioning smoothly for as long as it can.

Manufacturing or Installation Problems

Any less-than-perfect material or installation can cause the unit to fail before its expected lifespan. Therefore, you should go for the best to avoid your unit’s premature failure, and we here at Homeshield offer exactly that!

Age and Condition

The age and condition of your unit’s frame make a difference. For instance, an old frame that has been exposed to some sort of damage may not be able to hold the double-glazed glass as effectively as a new, well-fitted frame.

Chemical Cleaning

Sometimes, the chemical material used for cleaning the window affects the seals over time. Losing the sealing between the two panes can cause the total failure of the unit.


How long does double glazing last?

The lifespan of double-glazing units ranges between 20 and 35 years, depending on several factors.

For instance, your house’s location, temperature, as well as the general quality of installation, all will affect the longevity of your double glazing.

Fortunately, there are tell-tale signs that your double glazing needs replacing. For instance, if you notice condensation, white spots, cold air, or an increased energy bill, you need a replacement double glazed window.

New technological advancements have made double glazing more efficient and long-lasting than ever before, and with our team of trusted professionals, Homeshield are sure to provide you with the perfect service.


Still have queries, check out our frequently asked questions:

Do double-glazing units need maintenance?

Yes, double-glazing units require some maintenance to increase their longevity. 

Maintaining your double-glazing units entail keeping all the mechanisms, hinges, and locks in good shape by cleaning them frequently. 

In some cases, you may seek professional help to replace or repair them if they don’t work as properly as expected.

Do I need to Replace My Entire Unit?

In some cases, you have to replace the entire double-glazing unit. For instance, if you’ve noticed condensation and frame damage together.

However, in most situations, you’ll have to replace either the frame or the glass depending on the problem.

Can I only replace the broken glass in a double-glazed unit?

Yes, contrary to popular belief, you can choose to replace the glass only in your double-glazing unit. A professional can fit new double-glazing glass into your door or window frame. 

This option can be cost-efficient, as you don’t have to replace the frame as well – an excellent choice if they’re still in good shape. 

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