6 Questions Consumers Should Ask Double Glazing Companies – And The Answers

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Nick Dardalis

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Are you a consumer about to embark on buying new double glazing?  For some customers the thought of purchasing double glazing is not something they look forward to.  Typical reservations and negative perceptions of buying new double glazing will include:

  • Not knowing what is available out of the many products in the market
  • persistent double glazing salesmen that may not leave the house
  • pressure to buy on the night with seemingly too good to be true discounts
  • fear that the installation will go wrong and cause disruption to your home
  • the negative perception of double glazing firms
aluminium, pvcu or timber windows
With 12,500 window and door companies in the UK, you are bound to have questions.

The vast majority of double glazing firms are ethical and professional.

In the UK there are around 12,500 companies supplying doors and windows to the consumer, including the big four (Everest, Anglian, Safestyle and Zenith).  Generally speaking people do not set up in business to rip the customer off or carry out bad installations.  The home improvement industry is worth billions of pounds in overall sales across the entire supply chain in the UK and abroad employing hundreds of thousands of people.  Despite this, the image of double glazing firms and the people that represent them remains a negative one.

Visit any window company website, read any double glazing brochure and the messages across all publications will be positive and very similar.  Double glazing messages will be about customer confidence, selling a lifestyle and about transforming your home.

You will often read on websites, brochures and social media channels articles such as “questions to ask your double glazing firm” or “ questions to ask before buying a window or door”.

Some of these questions are of course important and pertinent.  But if one window company is extolling the virtues of what they do, their products and their brand, does that mean anyone else is bad? What is the fair and balanced alternative point of view to common questions or statements about double glazing?

6 Questions Consumers Should Ask Double Glazing Companies – And The Answers

  1. How long have you been trading?
  2. Are your fitters employed or subcontractors?
  3. Are your salespeople commission only
  4. Are your doors/windows/conservatories manufactured in the UK?
  5. Do you have a showroom?
  6. Are you a member of a trade body?

Does it really matter how long your window company has been trading?

You will often read companies promoting that they have been trading for 10, 20 or 30 years.  With many double glazing firms large and small having gone into administration in recent years, a solid history  is certainly something to shout about.

But this does not necessarily mean that a window company trading only a few years should not be considered.  Anyone who starts their own business does not set up to let down their customers.  If you’re concerned about a newer company have a chat with the owner or senior staff, you may well find that there are many years of experience behind the company.

“Buyer beware” is generally the principle with any purchase and the same is true of home improvements.  It could be argued that new companies will be even more focused on serving you well in order to build up the satisfied customer base and their testimonials.  Therefore the fact that a double glazing firm has not been trading for many years is not a bad thing.  Simply do your research.

Does it really matter if  a window company employs sub contract or self employed fitters?

The answer is no.  A window company may promote that they are somehow at an advantage over their competition because they employ their own window fitters and don’t use subcontract labour.  This doesn’t mean they’re lying but how do you actually know this unless this is proved to you?

vevo windows peace of mind service to homeowners using local, community based and reputable installers
Even self employed fitters are  local, community based and reputable installers

What is true is that the home improvement industry is very buoyant presently with many firms reporting excellent trading.  A byproduct of this success is that many double glazing firms are  struggling to find good window and door installers to keep up with demand. With window fitting being a trade that few people choose as a career, how do these firms find additional labour?

There is little by way of apprenticeships  in door and window installations either.  Therefore when a window company is busy and needs installers it is natural that they will outsource this labour just like any other business would.

Here are some facts about sub contract fitters:

  • Many window companies actually use subcontract self employed fitters that are given branded window company vans.
  • Reputable self employed window fitters rely on regular work for their living and many choose to work for good window companies to keep earning.
  • The quality of window company installations speaks for itself regardless whether fitters were employed or self employed.
  • The national companies may pay their fitters on a “per window per day” basis hence possible issues with bad installations.  Local firms pay day rates instead.
  • Many self employed fitters have been working for over 20 years and many for the same company. They are very good at what they do.
  • Many window fitters that work for the national companies often approach small local firms because that is who they would prefer to work for.

Ultimately it is up to each window company to extol the virtues of their own installation teams regardless of whether they are employed or self employed.  It may build trust that fitters are employed by the company but the reality is the vast majority of the double glazing sector will use self employed fitters.  So if a window company promotes that it employs its own fitters, this does not mean you will necessarily get a bad installation elsewhere.

What you should know about double glazing salesmen.

our industry should look at the way it employs double glazing salespeople
The double glazing salesman may be the first link you will have with your window firm.  Ask questions and do your research.

The double glazing salesman is sometimes derided and ridiculed by the public but from the comments and emails received into this website, sometimes there is a good reason.  The large double glazing firms employ commission-only salespeople with minimal training on products as they largely supply a limited product range.  The majority of the training given to commission-only salespeople from the national double glazing firms is focused on sales tactics and closing the sale – preferably on the night.

By comparison, the independent and local double glazing firms whilst some will employ commission-only salespeople, will rarely put the pressure on their salespeople in the way the larger companies do.

Beware the double glazing salesman that will attempt to rubbish any other product.  Whilst modern double glazing does of course differ in specification from product to product, the truth is that with British Standards, CE Marking, Secured by Design and Building Regulations, all window and door products available today will meet or exceed standards for manufacturing, security, building regulations, longevity of foils, colours and glass.  Yes some products are far superior to others but by and large, current industry standards are met.  All manufacturers publish the performance figures and reports for their products so it is very easy if you do your research to compare like for like products.

Beware also the double glazing salesman that tells you aluminium suffers from condensation or that timber rots. All products regardless of material come with guarantees and routine maintenance guidelines to ensure long service life.  Disregard anyone that tells you their products are maintenance free.  No door or window is a “fit and forget” product and all will require some form of cleaning, lubrication or adjustment at reasonable intervals during their lifespan.

The way the double glazing industry chooses to employ and remunerate its salespeople is largely to blame for much of the negative perception and the pressure salespeople feel to close a sale on the night.  As a customer you should exercise buyer beware and ensure anything a salesman may promise is agreed in writing.  Our experience in this industry has proved time and again that many sales people will promise the earth in order to close a sale.  A salesman will rarely highlight anything negative. Check your contract terms and conditions and if there are extras to your job that a standard window contract may not have room to list, ask for these to be written separately and signed.

An excellent example is bathroom tiles.  It is sometimes the case that bathroom tiles on the window reveal may crack when the old steel window is removed.  A salesman may promise that the tiles will be replaced but how can tiles in old properties be replaced if they are no longer made? For a window company this is a major problem but for a salesman it will not be brought up as a possible problem should this happen. Most double glazing salespeople will rarely have contact with their customers after the contract is signed as their job is done.

Many salesmen believe certain responsibilities are down to the surveyor and many surveyors believe it is down to the salesman.  This conflict in who should finalise the specification can cause problems for the customer.  Often customers will complain the window handles are different from what they thought, window profiles should have been chamfered and not ovolo, glass patterns in bathrooms are different from what the salesman said and so forth.  You must remember that double glazing salesmen are not not surveyors or fitters.

The surveyor may find something upon survey that counteracts something the salesman may have told you.  The structural nature of your property may prevent the product you thought you were having being installed.  It is very important that you check your survey and not let your surveyor just get on with it.  Ask for a copy of the survey and ask questions if you are unsure about anything.  Similarly for a window company it is very good practice to get your customers to sign the survey as this will avoid issues upon installation that something was not as they thought.

Does it really matter where your windows and doors come from?

whether you are a manufacturer or a retail window company, sapa door kits can bring you many benefits
Aluminium doors and windows remain hand crafted after cutting and machining.  PVCu windows are now largely mass produced.

Over the last 10-15 years the number of small PVCu window manufacturers has diminished to very small numbers. This is because “super fabricators” as the double glazing industry refers to them set up in business to manufacture thousands of windows a week.  The very low cost of these windows meant window companies could buy in the same window system they were manufacturing for much less than it cost them to make it!  With machinery, factory labour and factory overheads this did not make it viable for small to medium sized firms to continue making their own PVCu windows and doors.  Once a marketing advantage that a company made their own windows this is no longer the case.

Aluminium windows by comparison will never be supplied by super fabricators.  Whilst there are large trade manufacturers of aluminium windows in the UK, the hand made nature of manufacturing aluminium means the supply chain is more specialist and less mass produced.  PVCu windows are mass produced, aluminium windows remain a hand made product.

Therefore with few exceptions such as timber look plastic windows or specialist sash windows, your PVCu windows will probably come from a large super fabricator.

Some window companies claim on their websites that competitors windows come from abroad.  This is highly unlikely and should not be believed unless proved.  There are some timber windows that do come from Europe but virtually all windows and doors are manufactured in the UK. The profile itself used to make the windows may be extruded and produced abroad, but the physical windows will be made in the UK.

As long as the product quality is good and you are getting the product you want, there is little to fear about where your windows will come from.

Does it really matter if your window company does not have a showroom?

a range of entrance doors are available to suit all types of property.
If you are buying windows, doors, bifolding doors or patio doors a visit to a showroom is essential.

The major national double glazing firms such as Everest (Turnover approximately £150m), Safestyle (Turnover approximately £140m) and Anglian Windows (Turnover approximately £200m) do not have showrooms.  With such multi million pound turnover this proves that these large window firms clearly have no need for showrooms.

It also proves that there are hundreds of thousands of double glazing buyers happy to buy from commission only salespeople that they will meet only once.  It proves that they are happy to make a buying decision based upon someone in their home presenting a battered tiny little window sample, some brochures and small pieces of glass.  It proves that many people commit to spending thousands of pounds on this basis.

Double glazing remains one of a handful of industries where customers are happy to commit a lot of money without ever visiting a shop or seeing the actual full sized product they are buying, see it installed or visit the premises of the company they are about to do business with.

Our advice is to always visit a double glazing showroom.  Especially with large products like entrance doors, bifolding doors or patio doors, surely it makes absolute sense to see these large products installed and functioning to be absolutely certain you are getting the product you want?

Visiting a showroom makes absolute sense to get a feel of your double glazing supplier, their staff, knowledge and range of products available.

However, it is also fair and right to also point out that there are many window companies all over the UK that have been trading for a very long time without any showrooms at all.  They too provide excellent products, high quality installations and continue to trade professionally, ethically and are financially sound. So whilst there is an advantage for window companies that do have have a showroom we would also recommend you consider the local firms that do not.

How important are memberships of the Glass and Glazing Federation and other professional organisations?

The Glass and Glazing Federation is an important representative of the UK glass and glazing industry and does excellent work in representing its members, working to raise standards as well as helping members of the public.  Many of the UK double glazing firms choose to be members of the GGF  for the help, support and representation it provides them in many areas of the sector.  The GGF is also very useful to consumers ensuring they have adequate consumer protection.

We would always recommend that you do your research to ensure you are well protected before signing any contract for new double glazing.  The financial stability of the double glazing firm is important as you will have to pay a deposit and you will expect completed work as a result.  Insurance backed guarantees also provide protection for consumers should a business cease to trade.

There are also other organisations such as the Double Glazing Conservatory Ombudsman Scheme that also exist to provide consumers and window companies levels of protection, help, advice and support should things go wrong. In the unlikely event that you are not happy with your window company, there is help.

It is not a legal requirement to be a member of any professional organisation, although regulations now exist for the certification of installations via FENSA or Certass.  Indeed there are many window companies that trade profitably, responsibly and reputably without being members of the GGF or other trade organisations.  Therefore if a double glazing firm is not a member of any professional organisation, this does not instantly mean they are not reputable.

With “consumer protection” being the focus of these Organisations a negative implication exists that customers somehow need protecting from double glazing companies! This is not the case.  What these organisations provide is information, support and advice should there be problems with the work carried out.

The important point to remember is reputable window companies do not set up in business to take your money, carry out shoddy installations and leave themselves liable to claims, litigation and involvement of arbitrators and others.   Similarly most window companies will do their utmost to resolve issues fairly, promptly and responsibly. Window and door installations generally go well but the onus is also on you the consumer to be fair in your dealings with your window company.

The removal of windows and doors and the installation of new ones is significant building work and not as simple as fitting a new carpet.  Vital elements of your home’s structure are being removed and replaced and it is reasonable to expect that when this type of work is carried out things sometimes won’t go to plan.

Consumers should also bear in mind that double glazing is one of the few products that they can obtain before full payment.  In most other business transactions you are expected to pay for your goods before you receive them not after.  Certain double glazing firms have absolute faith in their work and won’t even ask for a deposit wishing you to pay when you’re happy.

In the same way the public complains about double glazing firms, we too complain about how we are treated by the public who see it fit to withhold thousands of pounds because a handle cover may be missing or a piece of glass is marked.  In the same way you expect your window company to be professional in its dealings with you, so the window company expects you to be fair with regards to installation issues and payment upon installation, whether this is partial or complete.

the new origin aluminium window is a bespoke window manufactured to the same exacting standards as their successful bifolding doors.
Home extensions with large windows and bifolding doors are vogue.  Windows and doors such as these made by Origin can play a part in how you use your home.

Are you really being sold a lifestyle?

Is your window firm or salesman is trying to sell you that double glazing will transform your home or give you a dramatic change in lifestyle? This must depend upon what you want your new windows and doors for and very importantly what they are part of.  Windows and doors can do nothing on their own without the building they are being fitted to, the room they are part of and their intended use.

If you are a landlord refurbishing a rental property the reality is you will want the cheapest possible windows that will simply do the job of providing a solution to your old windows and making your rental property lettable. You do not care about bells and whistles.

It is highly unlikely as a professional landlord that you will care about energy efficiency, U Values, aesthetics and what your window looks like or whether the new windows will somehow improve the lifestyle of your tenants.  Professional landlords in particular are in business.  In the same way smart landlords will fit the budget carpet and budget kitchen in a rental property, the same can be said for the windows and doors.

If you’re a homeowner installing new windows and doors in your own home it may be a different matter.  Again if you are restricted by budget you may simply want the cheapest and best windows you can afford only to replace your old draughty or rotten windows.

If you are building your dream extension, then naturally the purpose of the extension will be to give you a larger kitchen, an additional family room or simply more living space.  You may be having a new kitchen, a larger living space, roof lantern, windows and bifolding doors.

With building and design trends moving to more natural light, the glazing in your extension is important but it is the windows and doors in harmony with the whole extension and your fixtures and fittings that may give you the change of lifestyle and alter how you use your home.  But not on their own.

You can buy double glazing with confidence

We hope the above has given you a balanced and alternative view to many of the typical questions and statements made about double glazing.  The consumer today has much more information at their fingertips than ever before.  Gone are the days when you only relied upon a window salesman to tell you what products where available and what you could have.

There are now a multitude of new windows and doors in aluminium, timber and plastic that will blend in with your property whether you are looking for simple window replacements or something more bespoke.  Please use the contact form below if we can assist you with any aspect of buying new windows and doors or if you would like information about good double glazing firms where you live.

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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!
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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.
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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
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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
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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.
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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.
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12:28 14 May 23
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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!
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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.
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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!
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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.
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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.
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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!
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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
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11:45 13 Sep 22
Nick has been very helpful on signposting me to a number of partner organisations for steel/aluminium doors.
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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.
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13:14 14 Aug 22
received a prompt reply to my query,and helpful information from ATS