How to replace Crittall Windows with Aluminium

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Nick Dardalis

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Does your home currently have old metal windows or are you looking to replace Crittall® Windows? There are some excellent and very experienced companies such as The Heritage Window Company specialising in steel window replacements. Crittall® is, of course, the origin provider of steel windows with some outstanding products in their current range. These modern steel windows come with the latest in security, colour choices and meet current Building Regulations for thermal performance.

However, what do you do if the budget does not stretch to steel windows? Aluminium windows will be cheaper, but there are things to consider as not all systems will be ideal.

replace crittall windows
This art deco house built from scratch features windows made by The Heritage Window Company

Using Aluminium to Replace Crittall® Windows

First of all, we always suggest using the original product.  Only by replacing a steel window with a new steel window, will you get the best result.  In aluminium, look at products designed as steel-look or steel-replacement systems. Some well-known steel windows such as the W20, W30 and W40 types come with an aluminium option in some systems, similar but not exact. The Benenden range from The Heritage Window company is currently the slimmest aluminium window designed for the replacement of old metal windows.

We’ve put together some information on the current range of aluminium systems that offer a steel replacement window range to help you understand what is available in the market. We also suggest you compare the visual, performance and other differences between aluminium and the authentic steel window.

Can new aluminium windows be fitted to existing frames?

Yes. Whether you have timber, hardwood, oak or stone surrounds, the right aluminium window system can be fitted to your existing surrounds.

However, you may need to consider the option of replacing these frames as well if they are no longer in good condition. It is often the case that the subframes the existing windows are fitted to appear in good condition but only when the old windows get removed can you spot the state of the timber frame.  An experienced window surveyor should be able to advise you on the condition of your existing window surrounds.

The advantage of retaining the existing frames of course that that internal decoration and external render won’t be disturbed minimising the work involved.

Don’t forget that modern aluminium window replacements also come with a direct fix method.

Are aluminium windows energy efficient and secure?

With front to back dimensions of over 50mm with most systems, this means Crittall replacement windows in aluminium can accept 24mm or 28mm units that are available with excellent specifications and an A rating if required.

It is important to remember that with such a slim frame, much of the improved Window Energy Rating will be down to a proper glass specification.

Some systems also have a sloping glazing bead designed to replicate the original putty line of the old metal windows. This putty line look can also extend to the glazing bars.

These modern aluminium systems also allow multi-point locking, and secure window handles to be incorporated. Specialist suppliers will also be able to customise the windows with period handles and even projecting hinges typical of the original ones used.

You can even have peg stays, butt hinges or the more recent concealed friction stays.

What about the glass on old Steel Windows?

The right window installer will also take care of the small details such as those found in the original glass. Ask about the type of lead used in the leaded lights and ensure it is the antiqued soldered lead.

If your original windows have external and internal glazing bars, ensure that these also replicate the putty lines of the old windows if possible.

How to replace Crittall Windows with curved bays or “Sunshine Bays”.

art deco steel window replacement.
An aluminium alternative to the desirable Sunshine Bay, although steel remains the best option.

In many Art Deco Homes, you will find the bay windows featuring curved glass on the sides. These are also known as sunshine bays.

These curved windows are very typical of the period. In recent years many homeowners chose to replace these with flat windows angled by a modern bay pole, but the effect is not quite the same.

If you want to replicate the curved glass and curved horizontal window frames, this will be a much more specialist job requiring the services of experienced aluminium bending specialists and a specially made curved glass unit.

The cost will be much more than a flat glazed window; however, the effect of the finished window you will find well worth the extra price.

So what can you expect with new aluminium windows?

If you choose the right window installer and one that is experienced in replacing old steel windows with the right aluminium alternative you will benefit from:

  • Modern Windows that replicate the originals
  • Retention of original features
  • High Security
  • Double Glazing
  • Retention of your existing window surrounds
  • High quality powder coated finish
  • A reduction in heat loss and condensation.
  • Reduced window maintenance costs.

Once again, we must stress that nothing is as good as, or compares to an authentic steel window.  Despite this being an aluminium website, we encourage you to look at steel windows seriously and compare.  They may be more expensive, but you get the original product with an altogether different look, construction, specification and service life.  They are better.

If you would like more information to replace Crittall® windows or other steel products, use our contact form to get in touch and ask a question.

Crittall® is a registered trademark of Crittall Windows Limited which is unconnected to the Aluminium Trade Supply Website.

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16:42 30 Oct 23
Nick responded incredibly quickly to my enquiry (on a Saturday too!), and was able to offer invaluable advice on both aluminum systems and manufacturer / suppliers. Thanks Nick!
chris steerchris steer
16:18 09 Oct 23
Had a meeting with Nick during the grand designs show. Was extremely helpful and professional would highly recommend
Chris WesthorpChris Westhorp
19:55 13 Sep 23
Extremely helpful with pointing us in the right direction to find the products we required and suggesting firms that could reliably fit them.Nick was quick to reply and very detailed in his advice.Highly recommend reaching out to them.
Cathy GreenwoodCathy Greenwood
07:03 11 Sep 23
Update - A second email to nick for help on bifolds resulted in a detailed informative reply even on a Sunday ! This guy is so knowledgable and helpful .I approached Nick for an independent view on sliding doors v bifold and the different brand options . His reply was extremely detailed and prompt and allowed me to navigate this often confusing world in a much more informed way . Thanks so much Nick
Anthony CraigAnthony Craig
12:45 05 Sep 23
This is a must site for anyone looking for advice. Great service and very quick answers to questions. Nick has been of great help quiding us through the maze of aluminium products. Thank you
Philip DuffieldPhilip Duffield
20:24 26 Jul 23
I contacted Nick @ ATS for guidance on what aluminium sliding door systems would be suitable for an opening in an extension that is going to be both wide and tall. He came back really quickly with very detailed and incredibly helpful advice. He is clearly extremely knowledgeable about the systems on the market and their respective features and capabilities. If you’re feeling a bit lost by the overwhelming range of choices out there, I’d definitely recommend contacting him.
Dariush HekmatDariush Hekmat
17:25 19 Jul 23
Nick's advice is great. He is always quick to respond and spends time on responses, which really help to make an informed decision.
Alan FosterAlan Foster
07:51 12 Jul 23
Absolutely fantastic. Asked for advice about replacing Crittall (?) windows late last night and early this morning received 3 great suggestions and contact information for suppliers
Rachel LauRachel Lau
09:24 16 Jun 23
Fantastic website full of valuable and pragmatic advice about product selection and comparison: no other website gives information like this. Truly written for public interest. Don't hesistate to reach out to Nick via the mailing system. He responds very quickly, is friendly, and has very sound and high knowledgable advice. I have already shared this with my friend planning her own grand design.
guard Charlieguard Charlie
12:28 14 May 23
I emailed this company just on the off chance they could help me with new magnetic sliders for my patio door. They were not able to supply those but were so very helpful providing me with the name of a company who could. I am so very grateful at the great service. Dare say customers must be very happy. thank you so much.
Benjamin LewisBenjamin Lewis
10:06 04 May 23
Nick is very helpful indeed. Extremely knowledgeable on bifolds which was in relation to my query. Great website as well, some very useful articles. Particularly appreciated the article that lists all the major bifold options in order of their sightlines! Thank you!
P JonesP Jones
08:07 15 Apr 23
I asked Nick some questions about an installation we were considering and he replied within hours with some very useful suggestions that will probably lead us to using a different make and supplier. Thanks, Nick. Great work.
Nicholas WallNicholas Wall
13:18 02 Apr 23
Looking for fair and honest expert advice on all aspect of aluminium windows and doors? These guys will arm you with all the information you need to make the RIGHT choice in a highly complex, crowded marketplace. post a question and you will get a very quick professional answer you can rely on being based on fact. Thanks guys!
Giorgia SiriacoGiorgia Siriaco
16:25 21 Mar 23
After a lot of research to find doors that would meet our unusual size requirements and feeling increasingly uncertain about the best way to spend our small budget, I stumbled on the ATS website, and I'm so glad I did! I contacted ATS to request advice and Nick promptly replied with a wealth of information, providing us with options and relevant contact details. I only wish I'd found them sooner!
Carol NortonCarol Norton
10:01 17 Mar 23
I've been so confused about how to achieve the look I'm after, and going round in circles with various window/door companies, trying to get away from the huge chunks of plastic currently around my windows. I didn't expect an email to a company found through a Google search to really help - but I was desperate, so I tried. I'm SO glad I did. Finally I have clear explanations from ATS of where I've been going wrong, exactly what I'm looking for, and a list of local companies that might be able to provide it! The response has excelled my expectations and I feel as if I'm finally inching closer to a home with which I'll be happy and comfortable: thank you.
David NunnDavid Nunn
20:54 14 Mar 23
It is rare that I write reviews, however after my very positive communication with Nick - enquiring about suitable slim sash aluminium windows for my project, I felt that a review was definitely warranted. I can reinforce the many positive reviews posted so far, Nick was very quick to respond, providing comprehensive detail, with excellent independent advice.In summary, great service, thank you Nick.
Chantal AuerbachChantal Auerbach
13:04 09 Mar 23
Nick from Aluminium Trade Supply was incredibly helpful informative and pleasant to deal with. He responded quickly to emails and was very knowledgeable. Highly recommend being in touch with Nick if you are considering new aluminium windows or doors.
Lee JonesLee Jones
20:21 22 Feb 23
I dropped Nick at Aluminium Trade Supply an email re high security slim sightline bi-folds and their alternatives and he responded that quickly (and so comprehensively) that I felt bad I’d not paid him for his time!Nick Sir your product knowledge is outstanding and you are providing a level of service that goes wayyyy above and beyond expectations. I’ll definitely make sure I mention Aluminium Trade Supply to anyone I encounter looking for a fenestration solution 🙏🏼
15:13 13 Feb 23
We are looking to replace some old UPVC patios doors with aluminium ones. The ATS website is a great source of advice in an area where clear information is sorely lacking. Having used the website, I then followed this up with a number of specific questions relating to our search, and Nick came back very quickly with clear, detailed and very useful advice.I have been very impressed with both the website and with Nick's advice. My only regret is that I didn't come across ATS before replacing various windows in 2021 - I'm sure it would have saved me a lot of grief and money! Thanks again Nick.
Azza McCabeAzza McCabe
17:47 01 Feb 23
So impressed with this company.Responded to my query quickly andgave valuable advice. Nick was extremely helpful and we were able to move forward with our project.
Adri LoloçiAdri Loloçi
11:21 08 Jan 23
Nick was super fast to respond and provided some great recommendations. I would recommend this website to anyone looking to find bifold or sliding aluminium doors.
Stephen HoustonStephen Houston
16:16 03 Jan 23
Looking for aluminium crittall style internal door and external patio French doors. Noted good reviews and thought would ask for advice. Comprehensive reply with excellent independent advice and lists of fitters who could provide products and installation. Great service.
Inga GeachInga Geach
08:25 21 Dec 22
Nick from Aluminium Trade Supply has been extremely helpful with navigating the jungle that is aluminium glazing for our upcoming extension project. His advice was prompt, detailed and always impartial. Very grateful for your input, thanks Nick!
Amanda BurtonAmanda Burton
10:54 16 Dec 22
Brilliant website and an excellent service. Nick provided not only detailed advice and supplier contacts, but highlighted the considerations of various products so I could make an informed choice. Our Sunvista minimal sliders were fitted this week and I couldn't be happier, stunning. Thanks once again for your advice and recommendations, invaluable!
Keith BarnesKeith Barnes
17:18 10 Dec 22
Very helpful advice given to my question, including the name of 3 different companies that i could try for the product being enquired about. Many thanks
Munim ChowdhuryMunim Chowdhury
11:45 13 Sep 22
Nick has been very helpful on signposting me to a number of partner organisations for steel/aluminium doors.
SUSAN wallaceSUSAN wallace
17:26 31 Aug 22
My experience with this firm was exceptionally good and this is notalways the case as a female, dipping a toe into technical waters.I was spoken too with courtesy and at a level that helped me consolidate what was needed .On top of that I was given a list of companies and places where I could obtain the type of product I needed.I could not thank them enough and would certainly go there again and reccommend others do too.
Paul SalterPaul Salter
22:39 22 Aug 22
Contacting Aluminium Trade Supply is like contacting the Oracle direct. Advice is always comprehensive and balanced. On multiple occasions they have provided me with options that fully meet our objectives. Many thanks.
Nick McCormackNick McCormack
20:25 14 Aug 22
Really helpful and useful came back to me on a Sunday with some invaluable information. Highly recommended.
ray addisonray addison
13:14 14 Aug 22
received a prompt reply to my query,and helpful information from ATS