A Look at Secondary Glazing Prices

Prices For 2021

Pros and Cons + Questions Answered

Get a Custom Quote Online

Part of Our Windows Guide and our Insulation Price LIst Price Guide

Secondary glazing is a popular option in the UK, and there are many benefits over regular double and even triple glazing installations.

It’s quicker to install, cheaper than many other glazing types and is more environmentally friendly too.

With better sound insulation and a warmer home, secondary glazing is a perfect option for many homeowners.

But how much does secondary glazing cost? How long does it take to install? And are there any negatives to this type of glazing?

We Asked 29 Glazing Companies How Much They Charge to Install Secondary Glazing

See an average of their prices and get your custom quote

What is Secondary Glazing?

Secondary glazing is a separate pane of glass inside a frame that’s fixed in front of your existing window.

It can be installed in front of old single-pane windows as well as double or even triple glazed units.

The most popular choice is sliding secondary glazing but fixed, hinged, or even lift-out panels are available.

There are many benefits to this type of glazing. People often choose secondary glazing to eliminate drafts and provide an extra layer of sound and thermal insulation to their windows.

Bedrooms are a common place where you may find secondary glazing as it’s ideal for those that need to sleep during the day.

Secondary glazing

An example of sliding secondary glazing by UA Glass

How Much Does Secondary Glazing Cost?

We contacted 29 window installers and asked them to provide us with prices to fit secondary glazing units in our home.

We provided measurements and photos of all our windows, and below, you can see how much this type of glazing costs to install.

We asked for two prices:

  1. The cost to install standard and also “acoustic” secondary glazing to our master bedroom.
  2. A price for the installation of 7 standard secondary glazed windows.

Below you can see the average price for this type of work; we’ve displayed the cost by region as prices vary around the UK:

Project 1 – Secondary Glazing to a Master Bedroom

This is how much we were told it would cost to fit a standard 4mm secondary glazing unit to a master bedroom.

There’s only one window in our bedroom and plenty of space in front of it to fit a secondary glazed unit.

We chose a sliding unit with 4 panels.

London Area£675£725
South, SW and Midlands£600£650
Outer Region and North£525£575

Below you can see the cost for the same as above but with a thicker pane of glass that also heavily laminated.

This type of glass is more expensive and is often referred to as “acoustic glass”. It’s perfect for noise reduction and soundproofing and is also more thermally efficient too.

London Area£875£925
South, SW and Midlands£800£850
Outer Region and North£650£700

Project 2 – Cost to Install Secondary Glazing to a 3-Bed House

We also asked for a price to install secondary glazing to an entire house.

Our property is a typical 3-bed home with 7 windows.

We chose standard sliding units with 4mm glass panes, which is the cheaper option. Thicker panes of glass will cost more.

This how much we were told it would cost us:

London Area£3600£3800
South, SW and Midlands£3400£3600
Outer Region and North£3100£3300

Key Benefits of Secondary Glazing

There are many benefits of secondary glazing, including:

Sound insulation – This type of glazing is popular with shift workers who need to sleep during the day. Even a basic 4mm panel can significantly reduce the amount of noise entering the property. Choose a thicker glass that sandwiches plastic for improved sound-proofing. (More ways to soundproof a room can be found here)

Very little waste – Your existing windows stay in place, so there’s no waste to dispose of and only minimal disruption during the installation. Secondary glazing is quick to install and better for the environment than a full replacement.

Efficiency  – A warmer home is a more thermally efficient home, and you can expect a reduction in your heating bills. The extra layer of glass can make a big difference, especially when fitted in front of double-glazed windows.

Affordable – As secondary glazing is easy and quick to install, it’s affordable and much cheaper than a full replacement.

Suitable for historic buildings – Owners of protected buildings often can’t remove the original windows. If they want to improve the building’s thermal efficiency, placing a new in front of the original is the only option.

Some Negatives:

There are some negatives to consider:

Windowsill space – You’ll lose some windowsill space as the secondary glazing is fitted in front of the existing window, so check how wide your windowsill is and whether there’s enough space to fit the new unit.

Cleaning – With an extra window pane, you have another two sides of glass to clean, thus doubling the surface area that needs to be wiped. Also, the inside surface of sliding panels can be difficult to reach.

Condensation – Because the space between the original window and the secondary glazing isn’t sealed, the humidity will be the same as the surrounding area, and as a result, condensation may form on the colder pane of glass. The cold, wet glass will be difficult to clean as it’s on the other side of the secondary glazing unit.

Our Advice

Secondary glazing is an excellent option for soundproofing a room but will work best if placed in front of a double or triple glazed unit. Here, it will significantly reduce the noise levels in the room, improve thermal efficiency, and condensation will be minimal.

While secondary glazing can be placed in front of single-pane windows, the noise reduction won’t be as good, thermal efficiency gains will be negligible, and condensation may be a problem.

Secondary glazing should only be placed in front of single-pane windows if there’s no alternative, i.e. the building is historic, and the original windows cannot be replaced.

Get a Price For Secondary Glazing Today

We hope you found our guide to the cost of secondary glazing insightful.

As every project is different, the best way to get an accurate price secondary glazing is to compare quotes from local firms and tradespeople.

Tap the button below to see how we can help you get a great price for your glazing project:

DIY Alternatives

There are two DIY alternatives worth considering:

  1. Shrink film.
  2. Magnetic panels.

We prefer the magnetic panels but the shrink film is good for temporary uses.

1) Shrink Film

Shrink film is a great option for drafty windows where you may only want a temporary and cheap solution.

The kit comprises thin plastic film, which is stuck to the edges of the window frame; the film is then tightened to create a firm barrier against the elements.

Use shrink film in winter when it’s really cold or as a short term solution until you can replace your windows or install a secondary glazing unit.

The photo here shows how it works.

2) Magnetic Secondary Glazing

This solution is cheap and easy to install but is a more long term solution than the shrink film.

Magnetic strips are secured to the edge of the window frame and the back of a plastic panel.

Then simply place the panel onto the window frame, and you have a cheap, transparent pane that keeps out drafts and noise.

Because it’s magnetic, the panel can be removed at any time and resecured whenever you want.

Secondary Glazing

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Secondary Glazing FAQs

When Were These Secondary Glazing Prices Published?

We sourced prices for sliding secondary glazing to an entire house and also to a master bedroom in early 2021.

Do The Prices on This Page Include VAT?


All of the prices on this page include VAT when it was charged by the companies we contacted.

Do I Need Planning Permission to Install Secondary Glazing?

If you live in a modern home then it’s unlikely that you’ll need to gain planning permission to install secondary glazing however, if you live in a listed building you may still need consent.

How Long Does it Take to Install Secondary Glazing?

You might be surprised at how quickly a professional installer can fit these units.

As the original windows are left in place, the work is straight-forward, and the installation of one window can take around an hour.

A house with 6-8 windows can be finished in around a day or, at worst, a day and a half.

What Options Can I Choose From?

The frame around the panes is available in several different colours, with white and brown being the most popular.

You can also choose from various pane thicknesses; obviously, the thicker the pane, the better it is to insulate and block sound.

You can also choose from glass or plastic panes, with plastic being cheaper.

We asked for prices to supply and install horizontal sliding secondary glazing, but there are other options, including vertical sliding units, lift-out, hinged and fixed units.

Where Can I Get a Price For Secondary Glazing?

We’ve partnered with of the UK’s leading online tradesperson vetting services where you can find approved, rated and reviewed window installers.

Get started here.

Discover More Price Guides:

By Quotation Check

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