Aluminium Windows: Pros, Cons, Costs and Buying Advice

a close up of a house with aluminium windows and patio doors
(Image credit: Sieger)

Aluminium windows are a popular choice for contemporary self builds. And while they look great, it's not just their good looks that make them so commonly specified, they also have a lot of benefits in terms of their practicality. 

However, when it comes to deciding on window styles, don't discount aluminium as purely for ultra modern builds — they look great in homes of all eras, from cottages and period renovations to extensions and more. 

The best aluminium windows also offer near unbeatable thermal efficiency, they need little maintenance and have great longevity — important if you're considering the trade off of the higher cost of these windows compared to other budget options.

But that's just the start of the key considerations you need to be mindful of when buying aluminium windows. Discover the essentials, including the pros and cons versus other window materials, the cost implication and how to source aluminium windows in our complete guide. 

What are the Advantages of Aluminium Windows?

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There are lots of reasons behind the ever-growing popularity of aluminium windows, including their good looks. 

They are:

  • Resilient to warping, corrosion and flexing
  • Lightweight and versatile but durable
  • Long lasting (up to 30-40 years)
  • Almost completely maintenance free
  • 100% recyclable
  • Aluminium windows provide fantastic insulation and keep in the warmth inside for long periods making them very energy efficient.
  • Available in a massive range of colours

a self build with a corner window

Aluminium windows from Thames Valley Windows and timber cladding creates a modern exterior to this modern self build.  (Image credit: Thames Valley Windows)

Aluminium windows use thermal break technology, meaning that they have a barrier between the inner and outer panes of glass. 

The barrier is made of a less conductive material and this stops heat from being transferred — they basically keep heat in and cold out. 

Aluminium windows are also useful for using in listed properties and in Conservation areas, as they can create styles of windows relatively easily. 

What are the Disadvantages of Aluminium Windows?

There are few, minor practical issues you'll need to consider with aluminium windows. 

This includes that aluminium windows can corrode when used for homes by the sea, thanks to salt in the water. However, you can specify a marine-grade powder coating to get around this issue. 

Also consider that window repair isn't so much of an option for aluminium windows, compared to timber windows. You can't paint aluminium windows, so scratches, dents and damage will need to be repaired professionally. 

However, the main drawback of aluminium windows is the cost. They are much more expensive to manufacture than uPVC windows; however, you need to balance this out with other considerations, such as their durability and longevity. 

How Much do Aluminium Windows Cost?

Are aluminium windows expensive? It is a common question amongst those considering them when replacing windows, largely because they are not known as being a budget option. 

It is true to say that aluminium windows are certainly not the cheapest window type out there, with costs around £400 - £600 per window. However, there is a good reason for this and when it comes to such an important element of your home, cheapest isn't always best. 

When it comes to achieving your glazing ideas, the appearance, durability and thermal efficiency of aluminium windows outperform many other window types, making this initial expenditure well worth it. You should also consider that, unlike timber windows, no maintenance costs will be required going forward. 

Aluminium window prices will vary depending on a number of factors, including the size of the property they are being fitted in and the number of windows being replaced/installed, as well as your choice of glazing. Of course the size and specification of the windows themselves will also affect the quotes your receive. 

bathroom with aluminium windows

Thermal efficiency is one of the main benefits of aluminium windows — in this project, designed by Adam Knibb Architects, the huge glazed openings provide views out over the garden.  (Image credit: Martin Gardner)

Which are Better, uPVC or Aluminium Windows?

uPVC windows (also known as PVCu) are certainly the cheaper option, being an estimated 20% lower than aluminium.

However, when it comes to quality, longevity and aesthetic aluminium windows tend to come out top. You also need to consider the value high quality aluminium windows could add to your home as well as the thermal efficiency levels.

Compared to uPVC windows, aluminium windows:

  • Won't warp or flex over time
  • Tend to last longer
  • Are low-maintenance
  • Won't discolour
  • Will add value
  • Will enhance kerb appeal
  • Offer better thermal efficiency

a self build house with aluminium windows

Grey aluminium windows from Kloeber offer a contemporary edge to this otherwise traditional brick self build. (Image credit: Kloeber)

Timber vs Aluminium Windows 

Wondering about the cost difference between timber and aluminium windows? Aluminium windows tend to be, overall, more affordable than timber windows made from hardwood, particularly those that are bespoke and come fully finished. However, when it comes to softwood windows, aluminium cost more.  

Advantages of aluminium windows over timber include:

  • A more contemporary look
  • No priming, sanding or subsequent painting
  • If cared for properly, aluminium can last just as long as timber but without the maintenance
  • No warping, rotting or movement issues

interior view from aluminium windows

Aluminium windows, such as these from Origin, come in a massive range of colours and configurations — and are perfect for contemporary interior schemes.  (Image credit: Origin)

What are Composite Aluminium Windows?

You may have heard of composite aluminium windows. These offer a compromise between the performance of aluminium and the characterful appearance and charm of timber and are often referred to as simply composite windows. 

They usually feature aluminium frames externally, with a timber finish on the inside. 

slimline fixed aluminium windows in a modern home

Large fixed glazing, such as this picture window from ID Systems, are possible when using aluminium framing.  (Image credit: ID Systems)

Do I Need Planning Permission for New Windows?

aluminium windows in oak frame self build

A combination of aluminium and timber frames have been used for this new oak frame home by Oakwrights — the result is a classic home with a modern feel.  (Image credit: Oakwrights © Richard Kiely)

New aluminium windows will not usually require planning permission. However, if you’re making window openings bigger or smaller you may need planning permission, particularly if it may cause overlooking issues.

Generally though replacing windows falls under Permitted Development but those living in following in the following may have restrictions:

If in doubt, check with your local planning authority.

renovation with aluminium windows

Aluminium windows wrap around the corner of this first floor living room to ensure the space is flooded with light and has great views. (Image credit: Jeremy Phillips)

How to Choose Aluminium Windows

There is huge variety in the quality of the various aluminium windows available. Good quality companies use prime billets in the manufacture of the windows, rather than cheaper scrap metal.  

The best aluminium windows are made from premium aluminium. They should have a smooth and consistent finish so watch out for pitting from when the profile has been heated during powder coating. 

The die should be polished – reducing corrosion and avoiding contamination on the surface – after each extrusion run to create a high quality finish.

composite windows in kitchen diner

Composite windows such as these from Internorm Ecohausare a good choice for those after the warmth of timber internally (Image credit: Jeremy Phillips)

Be sure to ask questions as to the grade of the aluminium used when shopping around

There are also significant variations in the quality of how windows are put together by suppliers. 

For example, when it comes to composite systems – which combine two materials, usually timber on the inside and aluminium externally – ensure that the external and internal frame elements are distinct (rather than, for instance, comprising a wooden frame clad on to an aluminium skin).

When comparing products, ask from where the key elements originated and where they were actually manufactured.

What Colours do Aluminium Window Come in?

Despite grey being an incredibly popular shade for aluminium windows, there are a whole host of other shades available. Many manufacturers offer frames prefinished in any RAL colour, which means greater flexibility when considering the kerb appeal. 

What’s more, companies tend to offer different finishes inside and out. This means while you might want a bright colour outside to a little cheer to a brick facade, paler colours can be chosen to compliment interior design on the inside, and vice versa.

That said, black, grey and anthracite reign supreme for more traditional and period homes as they can replicate slimmer traditional styles in Belgian doors and Crittall-style heritage windows.

grey aluminium windows

Aluminium windows are available in a range of colours — although Anthracite grey seems to still have top spot in the popularity stakes. This contemporary home features windows from ID Systems (Image credit: ID Systems)

What are Powder Coated Aluminium Windows?

Powder coated simply means spraying a polyester powder onto the aluminium to give a uniform and vibrant finish. Powder coating is typically considered to be the highest quality finish for an aluminium window as it is low-maintenance and weather resistant. Fixtures such as handles and hinges can be colour matched, too.

Although it won’t produce the same flawless and uniform finish as in a factory, aluminium can be painted on a DIY basis. Make sure the aluminium is properly cleaned, sanded and primed before beginning any paint work for the best results.

contemporary extension with white render

Powder coated aluminium windows are low maintenance and available in a wide range of colours.  (Image credit: Mo Photo c/o KE Design)

What are Slimline Aluminium Windows?

What are sightlines?

Sightlines are the visible parts of the window frame and the bars that hold the panes together. The slimmer the sightlines, the less windows impede on a view.

Slimline aluminium windows are hugely popular, with  very thin sightlines that allow for unobstructed views of outdoors and a sleek, minimalistic appearance.  

Today's aluminium window suppliers are all striving to offer the slimmest sightlines yet. However, before be sure to do some research on what’s actually available.

The renaissance of industrial-style and Crittall-style windows had seen a more design-led approach to sightlines. Delicate steel-inspired astragal bars create a contemporary and bold finish that rivals the coveted uninterrupted views to the garden.

‘Flush’ is the key word when choosing aluminium as the way the opening and fixed glass elements sit against each other side by side will make an impact of the slick look of the finished product.

aluminium windows with slim sightlines

Slim sightlines mean maximum views of outdoors can be enjoyed and plenty of natural light can enter your home. These enormous windows are from ID Systems (Image credit: ID Systems)

Where To Buy Aluminium Windows

The rule of thumb is to get quotes from at least three suppliers as there will no doubt be a huge range in prices. Ensure you understand what is included in your quotes (locks, handles, installation any required pressings etc) as additional extras might sway your decision. 

Bear in mind that buying windows is about far more than just costs: lead-in times can hugely impact your project. It’s important to be aware that a cheap buy with long manufacture and delivery times can delay a schedule and impact other aspects of a build.

Lead-in times are generally dictated by the manufacturers themselves and the industry standard is around four to eight weeks. However, if you’re in a pinch, Origin offers an optional 24 hour delivery promise.

Don’t forget, as most systems require specialist fitting, you will need to coordinate with a local approved installation firm if the window company doesn’t offer a fitting service.

dark grey aluminium windows

Dark grey is a popular aluminium window colour — these windows from ID Systems really complement the brickwork and stone that surrounds them.  (Image credit: ID Systems)

How to Clean Aluminium Windows

One of the best things about aluminium windows is the fact that they require minimal maintenance in order to retain their good looks and high levels of performance. 

Use a non abrasive cloth and a mild detergent in warm water to remove any marks from frames and dry with a soft cloth.

Occasionally, you might need to spray the hinges of your aluminium window with silicon spray to lubricate and ensure smooth functionality.

indoor swimming pool with aluminium windows

Slim sightlines are just one of the many benefits of aluminium windows. This swimming pool has a great connection to outdoors thanks to the full height windows from Origin.  (Image credit: Origin)

Are Aluminium Windows Secure?

Most windows and doors manufacturers aim to talk up their products’ security but now, thanks to changes to Part Q of the Building Regulations in 2015 and the Secured By Design standards, there are measurable ways of ensuring your choice ticks the boxes.

New builds require accessible windows (basement, ground floor and other easily accessible windows) as part of Part Q to be made to a design that has been shown through testing to meet the security requirements of British Standards Publication PAS 24:2012. 

Jason Orme
Managing Director

The former Editor of Homebuilding & Renovating magazine, Jason is an experienced self builder and has recently finished renovating his 1960s home. Jason is now Managing Director of Future PLC's Homes' portfolio, which includes UK-leading titles such as Ideal Homes, Livingetc and Homes & Gardens. He is also the author of The Self Build Dream. You can catch Jason in the seminar theatres and Advice Centre at many of the Homebuilding & Renovating Shows across the UK.