Who makes the best aluminium windows?

When it comes to windows and glazing for residential properties, finding the best aluminium windows need not be difficult. Whether you’re replacing dated windows or trying to find the best windows for a new extension or building product, this article tells you all the essential things you need to know.

We will also cover design and options, security, energy efficiency and colours.  There are some useful tips also helping you find the best aluminium windows where you also need French, bifolding or sliding doors to match.

How to choose the best aluminium windows.

best aluminium windows

Our advice is always to view your chosen windows in a showroom or exhibition. It’s the best way of understanding their make-up, styling and operation.

Although there are different types of opening windows, understanding windows is somewhat easier than doors. The construction of most aluminium windows is broadly the same as is the way they open and lock. Front, side or rear doors differ significantly in design and operation as there are hinged, sliding, folding or lift and slide types. Once you understand how they operate, you can concentrate on finding the style and design you like.

All aluminium windows are largely hand-made after machines cut the profiles and prepare the metal for locks and handles. You’ll find a similar construction in the corners, any mullions and transoms as well as how they open, close and lock.

The common features of most aluminium windows

Helping you understand aluminium windows, it’s first of all worth explaining the three common features of most aluminium windows. Importantly, whichever brand you go with, certain aspects of your new windows are the same. This then leaves you to choose the right product based on brand, styling or a specific design or functional requirement. These common features apply to both replacement windows and those for a newly built opening.

An explanation of the glass in aluminium windows

Similar to thermal insulation, meeting the required energy efficiency stipulated by Building Regulations also applies to your glass. Single glass does not meet these requirements. Therefore, you won’t find anyone selling single glazed exterior windows.

All of the best aluminium windows, including mid-range and trade windows, come with double glass units as standard. Most windows are designed for 28mm thick although 24mm is also acceptable.

Again as standard, expect to get a minimum glass specification of a soft-coat low-emissivity (low-e) coating, warm edge spacer bars and argon gas fill.  The low-e coating helps retain interior heat, the spacer bars are the edges of your glass and the argon gas instead of air creates a high performance glass in your windows.

How aluminium windows are coloured

Finally is the painted surface of your new aluminium windows. This advanced powder coated finish not only provides colour. It also protects the bare metal surface.

Your new windows come painted by specialist colour applicators under strictly controlled environments. Again, most products you see come with a surface finish of similar quality.

PVCu thermal break in a window
A typical thermal break in an aluminium window profile helping with energy efficiency

Understanding what thermal insulation in windows means

Also known as thermally broken, energy-efficient or insulated, all exterior use aluminium windows come with thermal insulation. In simple terms, the aluminium profiles are separated by a non-metal component (the thermal break) between the inside and outside faces of the window profile. Its job is to prevent the transfer of cold.

It’s this thermal insulation combined with the double or triple glazing giving you windows with good window energy ratings or U-Values but also windows that must meet current Building Regulations for energy efficiency. All windows meet these Building Regulations as well as safety, ventilation and means of escape such as in a fire. It’s highly unlikely you’ll find any aluminium window today without a thermal break.

Standards and specifications for aluminium windows

Further illustrating similar technical standards with aluminium windows, the following table shows window specifications and standards you’ll find most systems comply with.

For the critical components of windows like the profiles and the paint finish some systems companies produce in-house. Other systems companies outsource to independent extruders as well as specialist powder coaters. Specialist manufacturers produce rubbers and seals.  Your glass comes from glass manufacturers. Therefore, when it comes to the quality of everything that makes a window, you can regard quality as generally the same.

Again this leaves you to focus on style, design and personalisation options.

FeatureRelevant Industry Standard
Quality of aluminium profiles and extrusions Aluminium Alloy 6063.T6 to BS EN 755 Part 9: 2008 or BS EN 12020
Quality of polyester powder coated finishBS EN 12206-1:2004.
Quality of glassBS 6262 and Approved Document N
Quality of glassBS 6262 and Approved Document N
SecurityPAS 24, Document Q, Secured by Design, BS7950, BS EN 12209
Weather resistanceBS 6375: Part 1, Part 2 & Part 3:2009
Water resistanceBS 6375: Part 1, Part 2 & Part 3:2009
Air permeabilityBS 6375: Part 1, Part 2 & Part 3:2009
Quality of rubber gasketsEPDM Rubber manufactured in accordance with BS3734.
Quality of woolpile sealsBS 7386:1997
Polyamide Thermal BreakPA66 GF25
Anodised coloursSilver or bronze anodised BS3987 (AA25).

Who makes your new aluminium windows?

The vast majority of window installers do not make any windows. Instead, they buy them from specialist trade manufacturers. Some of these trade manufacturers work incredibly closely with their customers (your installer), with product training, installation support, pricing software and marketing.

Many installers are rightly proud of their relationships with the factories making your new windows and you can ask them to reveal either the supplier or the system.

There’s now the option for you to buy your new windows direct from some manufacturers and getting your builder to fit them. The obvious benefit is saving money although it’s unlikely you’ll get the same guarantee and support you would with the full supply and installation service.

Understanding your window ‘system’

The window system is the brand, the aluminium profiles and accessories. Also within the system is bringing the window to market, testing for security or weather performance. Aluminium windows systems companies invest substantial sums designing some of the best aluminium windows.

Then, the system including aluminium profiles, accessories and components are supplied by the systems company to its network of manufacturers. At the same time, these manufacturers are trained and supported by the systems company ongoing.

Your relationship is with your supplier and installer. They work with their manufacturer and supplier who in turn works with the systems company.

There are some exceptions to this with some systems companies also making their own windows also acting as suppliers. Origin is one of the best known brands of windows as well as sliding and folding doors working in this way. Anglian and Everest, two of the biggest names aren’t systems companies by they make their windows buying profiles from a systems company.

What does this mean for you? Often these systems companies come with decades of aluminium experience and frequently part of global groups. Schuco and Reynaers is an excellent example of two systems companies providing some of the best aluminium windows available, made through their network of manufacturers.

Windows for new-build homes and apartments

Buying a new home or apartment? These often come with brands you may not see in a showroom. Comar Aluminium, Senior Architectural, Kawneer, Aluk or Technal are examples of systems companies who’s aluminium doors and windows are found in many new build apartments and houses.

Commercial windows used by developers are no different from residential windows regarding specification, security and standards.

The aluminium window brands.

The following window brands (including specific variants) you can consider as some of the best aluminium windows. The reason they’re the best is down to several factors including who makes them, the overall design and quality, styling options as well as brand reputation. This is also reflected in the pricing.

Mid-Range WindowsBest Aluminium Windows
Stellar Aluminium WindowsSchuco Windows
Aluk Optio 58BW casementReynaers Windows
SAPA Crown Casement WindowSmart Systems Heritage Range
Comar Eco and EcoLT windowsSmart Systems Alitherm
Sheerline Classic and PrestigeOrigin OW70 and OW80
Everest Aluminium Windowsaïr MOD aluminium windows
Anglian Aluminium WindowsKeller Minimal Windows
Senior Architectural Windows Windows from IQ Glass
Kaye Building Systems KBSWindows from Panoramah
Deceuninck Decalu Windows AluK Optio 58BW ST steel replacement
Cortizo Aluminium Windows

The reason Reynaers and Schuco are widely regarded as the best aluminium windows brands is the multiple window solutions and different window products they design.

As well as this, Reynaers and Schuco have a portfolio of windows that are specialist and intended for specific requirements and uses. Examples include fire-proof, bomb and blast-resistant windows as well as maximum security windows for buildings where security or protection is critical.

It’s this expertise and window knowledge passed onto their windows and doors for dwellings making them some of the best aluminium windows available and the choice of leading architects and designers.

Of course, there are other specialist window businesses creating high-end architectural glazing but these are for Grand Designs type projects often different from the windows and doors most people want for their home or new extension. Examples include windows disappearing into the floor, guillotine windows, frameless box windows and many bespoke window creations.

Why the best aluminium windows differ

Even though some specifications may be similar, the best aluminium windows differ in the choices you get.

First of all is the choice of window style. This is an excellent indicator of good design catering for most project types. Examples include:

  • Different model variants meeting virtually any style and look.
  • Options including slimline, minimalist, contemporary, steel-look, heritage and traditional
  • Windows designed for larger openings resulting in larger panes of glass and more light
  • Windows with different colour options such as metallic, textured or wood-effect

Then comes the choice of hardware options. For contemporary or steel-styled windows in particular, a good brand provides period, modern or Art-Deco handles and accessories designed around creating the right style and appearance.

The choices you get are greater too. For instance aluminium windows by Origin come with probably the most extensive colour options for window handles. You can even match the frames exactly.

How to identify a good window from a bad

The good news is there are no ‘bad’ aluminium windows. Most brands share similar material specifications, quality and production standards or security specifications and more. It is incorrect manufacturing or installation creating a bad product and customer experience. It’s rarely a design fault with the window system itself.

Aluminium systems companies invest substantial sums in testing, certifying and bringing their windows to market, even those at the mid-range or trade price. Consequently, window problems come lower down the supply chain.

Some installers dislike certain brands as they find them complicated to fit. This is however of little concern to the homeowner customer. Or reports of leaking windows or those letting in drafts are again down to incorrect manufacturing or installation.

Stellar black aluminium windows

Security of aluminium windows.

As we mention, many of the best aluminium windows share standardised specifications.  Some windows come with enhanced security, others with more basic.  Therefore you can take it as granted that all major systems are independently security tested.  Ask to see the certification and check the credentials of the tested window.

The locks, handles and hardware found in aluminium windows.

The multi-point locks, window handles and components used to make your aluminium windows come from global or British companies that specialise in designing and producing hardware for windows and doors. The same applies to the seals, gaskets and rubbers.

Some aluminium systems use standard locks and handles. Other systems companies may work with more high-end lock companies such as Yale, Roto or Winkhaus, widely regarded as providing better locking systems.

It’s the window hardware where Reynaers and Schuco mentioned earlier that stand out. Schuco for instance provides automation with their window handles. Reynaers offers designer hardware even with anti-bacterial and high-end finishes and textures.

Recent innovations in aluminium windows

There are some noteworthy new windows offering you a different proposition to the established brands. These newer products offer different styling and sightlines.

aïrMOD by Everglade Windows

First is the new aïr MOD-Series collection of windows, under the Discover Air Brand from Everglade Windows.  The collection contains MOD Contemporary, MOD Flush Casement Windows, MOD Heritage for steel look, MOD Heritage Flush Sash, and MOD Tilt & Turn windows.  Designed for residential property, these come with the same impeccable product quality associated with the Air brand of sliding doors, bifolding doors, slimline patios and front doors.

Stellar Aluminium

Next, is the new and multi-award-winning Stellar Aluminium collection of windows and doors. Designed by Epwin Windows and available through professional manufacturers all over the UK.  Stellar aluminium windows promise slim lines, improved thermal performance, a flush casement design and an exciting new range for both homeowners and the trade. We’ve seen this window, it’s very attractive and well worth checking out. There’s also a great bifold offering fast-fit features and attractive lines.

Comar ECO LT

The new Comar ECO LT aluminium system is 100% British, very high quality and comes from a systems company widely chosen by building designers and architects for the engineering and high specification of their products. Comar ECO LT windows are available for homeowners through a quality dealer network with slimline frames, lovely looks and lots of pedigree behind the products.

The Sheerline System

Finally, launched in 2020 is the new Sheerline Windows range from Garnalex. There is a huge amount of experience and service behind Garnalex and the new Sheerline collection promises new, innovative and desirable aluminium windows for the home. The look and design of Sheerline promise great benefits for installers and an altogether different type of window for homeowners.

Sheerline won’t appeal to all installers as it’s construction is complex with a wrap-around beadless design. We’re also not sure how easy Sheerline will be to maintain in the future when it’s out of warranty and only serviceable by door and window maintenance/repair firms.

Decalu by Deceuninck

With a strong European design influence Decalu by Deceuninck is another system by a PVCu brand branching out into the aluminium marketplace.

We really like the steel-look version of this window as well as the overall aesthetic appeal. And Deceuninck as a system has a phenomenal reputation in the UK for quality and service so don’t let the PVCu heritage put you off. It’s a credible new aluminium window and door collection.

Why your windows don’t need to match your doors

The functionality of a window and a door are entirely different. It’s for this reason they don’t match. Therefore there’s no specific reason why the best aluminium windows from one brand need to have matching doors.

For example whilst Reynaers and Schuco design better aluminium windows, a customer may want a minimalist and super-slim sliding door – something not available with either of these brands. Similarly, Origin makes excellent slim or traditional looking windows but you can’t find a slide and stack bifold door in their range.

Therefore, it’s not a problem having windows from one system, your grand patio doors from another and even a front door from an alternative brand. It’s about choosing the right product for your property project.

There are just a few advantages to having windows and doors all from one brand:

  • A single point of guarantee instead of two or three
  • You like the idea of a consistent brand in your home
  • Your choice of brand or system meets your project needs
  • Often one brand saves money overall

Our top tips for choosing the best aluminium windows

  1. It does not matter if your doors and windows are different brands. Consider allocating more of your budget to premium doors and less to the windows.
  2. Ensure the information provided is factual. There is no ‘bad’ window on the market. Many share specifications and product standards.
  3. It makes sense to have combination windows mixed with doors from the same system. But not essential.
  4. Consider either opening options. Examples include sliding, reversible, opening in, pivoting, tilting and automatic windows.
  5. Beware the many re-brands of existing systems giving you the impression of being unique or exclusive.
  6. If you are buying different brands, here’s how to check your colours will match. 
  7. Remember there is an aluminium window solution for most projects. Contact us for advice or where to buy.

This article was last updated in May 2020.