Buying alu-clad windows and doors. Your Questions Answered

Alu-clad windows and doors are an attractive, innovative way to seamlessly integrate the beauty of timber with the durability and low-maintenance properties of aluminium. The combination of wood inside and aluminium outside creates not only stylish and long-lasting windows. At the same time, alu-clad windows and doors provide gorgeous design and fantastic energy efficiency. Their overall styling also makes them timeless and always in fashion. 

Here we answer some of the most common questions about alu-clad windows and doors.

What are alu-clad windows and doors?

inside view of white alu-clad windows and doors

Alu-clad windows and doors are mainly timber windows, where you get the natural wood inside and aluminium outside. Aluminium ‘clads’ or covers the window outside, giving the look of modern aluminium outside with the luxury of natural wood on the inside. Hybrid, alu-timber and composite are other names that describe alu-clad windows and doors.

The products mainly originate from the original Danish or Scandinavian companies, where these windows are trusted to protect properties from the very cold winters and keep houses cool in summer. 

Are alu-clad windows any good?

Most alu-clad window brands offer premium quality windows and doors that are widely used in some of the best homes, developments of quality homes and commercial buildings. They’re widely regarded as more luxurious than aluminium and equal to crafted wood joinery and the finest steel windows. 

They are at the upper end of the new windows and doors product range and are widely chosen by architects and quality-conscious homeowners. We provide the VELFAC and Rationel brands because we consider these two of the very best on the market. Velfac invented the Velux window first! You’ll also find alu-clad windows and doors frequently the products of choice on Grand Designs, eco-homes, low-energy buildings and Passivhaus. 

Does alu-clad cost more than aluminium?

Many factors affect the price of windows and doors, whether alu-clad or all aluminium. Sizes, colour, handle choices, glass specifications and where they are fitted can all affect the price.   Generally, alu-clad windows and doors cost more because of the design, engineering and hand-making that goes into creating these windows and doors. 

How long do aluminium-clad windows last?

alu-clad and composite windows in a new build house
Protective aluminium outside and highly insulated fine wood inside make these windows special.

Many leading alu-clad windows and doors brands market their products as having a 60-80 year lifespan when properly maintained. This is why aluminium and wood are such a great combination. Inside, the wood is protected by not being exposed to the elements in its natural state. Outside, the durability of powder-coated aluminium provides durability, protection and excellent colour choices. 

As a result, these windows are a genuine investment in new glazing, looking good, lasting for years and providing some of the best insulation and window performance. 

What windows are available in alu-clad?

You will find contemporary and traditionally styled casements, sliding and fixed windows and special designs, all available as alu-clad, composite or hybrid products. 

It is probably for windows that alu-clad is best and provides the most options. Whilst aluminium is available in tilt and turn, pivot windows, reversible windows and opening-in windows, these are hard to come by but very easy to do in these materials. 

What doors are available in alu-clad?

alu-clad windows and doors in a lounge setting

Front doors, single and double or French doors, doors with side panels and sliding doors are all available in alu-clad. You’ll also find some doors available in this material that you’ll struggle to find in aluminium, PVCu or timber. 

Doors are also available as tilt and turn, letting you use your door like a window for ventilation and a fully open door when required. You’ll also find French casement doors, slimline balcony doors, and sliding doors with a tilt-in ventilation design with some products. Another benefit is curved doors, available in our Rationel Forma range but nearly impossible to find in all aluminium. 

What are the advantages of alu-clad doors or windows?

There are several ways alu-clad windows and doors are better than other materials. First is their incredible energy efficiency, which is why they are widely used in low-energy buildings and new homes. Then is their incredibly long life compared to other window materials. Only steel windows arguably last longer. Another benefit is their natural look – nothing beats the warm touch and feel of natural wood inside a window. 

Finally, the sustainability and eco-credentials of alu-clad windows and doors are hard to beat, as is the styling that makes them always fashionable. 

What are the disadvantages of alu-clad doors or windows?

The design of alu-clad windows means a small number of products aren’t available. For example, ultra-slim windows and doors aren’t usually available with alu-clad, although VELFAC is widely regarded as providing this type’s slimmest windows and doors.   Bifolding doors and heritage or industrial glazing are also not usually available.  

How energy-efficient are alu-clad windows?

Very energy efficient. U-Values vary from product to product. However, you can expect U-Values of around 0.8Wm2K with a triple-glazed window, far exceeding the current building regulations’ requirements. If you want the best possible windows to save you money on energy bills, alu-clad windows are hard to beat for energy-saving. 

Why are the U-Values so low with alu-clad windows and doors?

Wood is a fantastic insulator thanks to the natural material and the fact that it is solid. Whilst aluminium and PVCu also come with low U-Values, the materials need multiple chambers, thermal breaks and high-performance glass. In fact, a triple-glazed window, like an alu-clad, can be 50% better than a double-glazed window depending on the model and glass type. 

Are alu-clad windows secure?

Very secure indeed. You’ll find most brands tested to the latest security standards, including PAS24, Document Q of the Building Regulations, the police preferred specifications and other European Security rates such as RC2 or RC3. 

Are alu-clad windows and doors sustainable?

If you care about the materials used for your new windows and doors, alu-clad is probably the most eco-friendly window you can buy. For example, VELFAC windows and doors use only FSC®-certified wood in the production of windows and doors.   Wood treatments are also the more environmentally friendly water-based method. 

Most of the material used for the aluminium outside of VELFAC windows and doors uses renewable energy sources, with nearly half recycled aluminium. Even the waste materials used in the production of VELFAC windows and doors are reused as much as possible, such as residual wood and sawdust swarf used for recycling and heat generation.  

Can I use alu-clad windows to replace my old PVCu or aluminium windows?

Of course. The window frame design on alu-clad windows and doors is designed not just for new openings but also for replacing existing ones.   

Suppliers and installers of Velfac and Rationel alu-clad windows and doors

Our range of Velfac and Rationel windows and doors is available for homeowners and on a trade supply basis for installers and the glazing trade. 

Contact us today for prices on these two excellent alu-clad brands, providing solutions for general window and door replacements and new build projects. 

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Peace of mind starts when you get in touch and lasts for years.

steve arundellsteve arundell
13:43 02 Nov 23
Chris and Andy listen to what we wanted and their team then delivered in spades.Great company well worth the effort to contact.
ArBa InstallationsArBa Installations
22:23 20 Dec 22
Posting from the view of an Installations company, C & A have always been a pleasure to deal with. Their process is very thorough and products are top quality. We use them for all our commercial doors and would highly recommend all their products and them as a company.
Paul DillonPaul Dillon
14:17 23 Nov 22
Great service. Top products. Thank you. C&A
Alfie TonerAlfie Toner
13:43 21 Nov 22
Great company to deal withQuick quotesPleasant staffGreat productsGreat customer supportDefinitely recommend
22:50 12 Jun 22
Couldn’t recommend this amazing company enough from start to finish the professionalism have been second to none. The quality of the work undertaken shows how much C&A take pride in there work. Thank You again
Gary WoodhatchGary Woodhatch
11:11 11 Mar 22
Have been dealing with Andy and Kim in the main at C&A windows for a few months now and the service overall has been great, quick quotes, lead-times inline with expectations and well presented and packaged goods. Great responsive aftersales assistance when called upon. Would recommend C&A for sure.
richard newellrichard newell
07:44 11 Mar 22
Always a pleasure to work with the people at c and a, very good communication throughout the process and most importantly the product is excellent.Highly recommended.

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