/ Home & Energy

Need new double glazing? Who would you trust to install it?

Only 7% of Which? members trust double glazing companies. Not that surprising when they’re renowned for dubious selling techniques, and steep price drops are a familiar part of the sales patter.

But building regulations mean we don’t really have a choice but to install double glazing when windows need replacing.

So when you’re shopping for new windows, should you trust the big names like Anglian and Everest, or should you go for a smaller, less well-known local firm?

Independent double glazers do better

Our latest satisfaction survey of double glazing companies found that that independent traders perform better and might even be cheaper.

The four big national companies (Anglian, Everest, Safestyle and Zenith Staybrite) are apparently leaving customers less satisfied than those who went with an independent double glazing company. As one Which? member said:

‘Local firms rely on word of mouth for their reputation and in a small town they cannot afford to let this slip.’

Local firms could be cheaper too

And, while you might assume you could get a better deal using a large firm, that’s not necessarily the case.

We sent a price questionnaire to Which? Local recommended double glazing traders to get the average prices you should expect to pay for different double glazing jobs.

We also sent the same questionnaire to Anglian, Everest, Safestyle and Zenith Staybrite. Both Everest and Safestyle declined to share their prices, with Everest telling us, ‘It’s no secret that we charge a premium price for our products’.

Anglian and Zenith both provided their prices, but we found that these were typically higher than those quoted by the independent traders who responded.

Problems getting double glazing

What’s more, those using local independents are also less likely to experience problems. Of those members who used local firms, around two thirds didn’t have a problem. But this figure fell to just over half for those who went with one of the big four companies.

The most common problems were: delivering the wrong parts, scratched glass, windows not fitting properly, installation taking longer than planned and installers causing damage to a property’s interior. Each of these problems were nearly always more common with the big four.

So, if you’re planning to get new double glazing, will our research influence whether you go for an independent or a big name? And if you’ve recently had windows fitted, who did you go with and how did they do?

WatchdogUK101 says:
25 November 2014

Local independent firms, aka family owned and/or family run, words that should strike absolute terror in the heart of potential customers, are far less willing to put right damage and/or faults – everything that is wrong will either be “within industry standards” or the fault of the customer!

Lynchy says:
26 November 2014

Bit of a sweeping statement. Local Independent businesses rely on word of mouth and reputation. If they kept creating unhappy customers the work would soon dry up. Unless perhaps you live in a densely populated area of total strangers like London where they can spread out their bad work.

My father in law creates Stone overlay driveways (Stonebond) and his customers buy him gifts and give him cards as he takes care to always do a great job. Everyone knows a good tradesman and a bad tradesman.

I suspect a lot of bad tradesman who’s work dries up sign up to large corporations like Anglian as sub contractors. Although on the flip side there must be lots of good Anglian installers/sub contractors too otherwise they would go bust.

But that’s the luck of the draw. At least with a local independent you know the individuals reptutation not just a brand name.

Anglian manager (nice guy) met me and we went over the work done on my house last week (had whole house double glazed) and agreed it is not acceptable. Sadly I have to have same contractors come and put it right. But I made sure the manager who works for Anglian will be there to oversee their work. Most important thing I did was witheld payment until I am happy was the work, otherwise I doubt I would have seen them again.


try working for them and you will see why problems exist
the actual nett cost of a window is generally 5% of retail list
never buy from the sales man even if they call the manager,all part of the script, you will, if you wait until next day get a call and a better offer
fensa registered and ? what it stands for is FENestration Self Assessment basically when you join the fensa club and pay your £7.50 a month subs you can then pass your own work.
Tip, get a local good carpenter to measure up purchase from a large manufacterer


your will need a certificate when selling your property so go to your local councils building control dept get the job surveyed by a proper surveyor who will issue a cert. if you used a time served chippie no problems and a large saving on cost .
Will mean a search online for a manufacturer and if it,s not just one window be ok
My best quote £3850.. completed for £ 1215 plus surveyor at£160.. and to same specification


Hi all, we’ve published a new debate about double glazers: “How do you choose double glazers you can trust?” – join in here: https://conversation.which.co.uk/energy-home/good-local-double-glazing-companies-trusted-traders/

defeated says:
15 January 2015

I had had very good service from Anglian some years ago and wanted a job done promptly so I went with them because sometimes local firms, although very good, have to juggle jobs and your job can take a while to be finished. It turned out to be a huge mistake and it has wiped out my savings. I ordered replacement rooftrim. They put it up over rotten wood . They are supposed to alert you to this but did not until the end when a fitter offered to get a mate to fix the last little bit for cash. At court they said I knew about the wood but it was an untruth. I asked for proof that they had told me but was not supported in my request. Their rep said he was at my house when the fitters told me . I challenged him and he was reduced to saying ‘I was there but you did not see me’ ! That was allowed. The judge (as expected) found for them because they put the stuff up and that is all they said they would do. Fit for purpose does not seem to matter, I have lost over £10k and a year of my life through them – not to mention, now, the will to live. Corporations rule.

Cherries says:
19 July 2016

Really sorry to hear about this, defeated. Yes, they do tell lies. I’m currently being sued by Anglian for the cost of a conservatory that did not comply with our agreement. I was willing to negotiate, but despite admitting fault – initially at least – they wouldn’t budge. I have to say that I’ve been completely taken aback by their willingness to lie and by the hostile and aggressive stance adopted by their solicitor. What a pity the solicitors’ regulation authority doesn’t seem to be interested in investigating her misconduct.

L Miles says:
1 February 2015

Suffice it to say that my list of complaints about our £20k Anglian windows/door installation covered 6 pages, very poor workmanship and one of the installers even asked me extra, in cash, to install the door he had trouble with! My biggest beef is re the garage door, admittedly out of warranty at the time of complaint, but the problems of poor installation which eventually came to a head were very basic faults of engineering which I have had to patch up myself. I did receive a visit from an Anglian rep after complaining who agreed 100% with all my criticisms but these were rejected out of hand by his Head Office who insisted I’d have to pay for any repairs, in spite of the mess they’d made of the job. As for getting through to an Area Manager, forget it, you HAVE to go through their Customer Services Dept.

Ambrose says:
23 March 2015

I can only sympathise we have had over 6 months of hell with Anglian . For a two date fit . Seven fitters have been to site. In operant .The fitting was atrocious ,they placed windows out of plumb out of centre completely unsealed and used internal caulking to place external trims which just pealed off . They did not support the front bay which caused the upper walls to crack and , the bedroom walls were damaged. They came back to do remedial work. To the glazing on several occasions. But did further damage and in the case of the bay’s made it worse and cracked the patio door frame . Apart from the manager nearly all the fitters lied and in one case deliberately covered up a serious structural defect, ie they did not place supports to hold up the bay .To the managers credit he employed a very good contractor to repair the initial building defects I employed a fenestration engineer to give an independent report for the likely court case , he has discovered the glazing is not as specified and around 25 % of the units are not gas filled . I have kicked Anglian off the job and having their windows replaced by a local company in fact today I have a full photographic record . Had I not been a surveyor myself they would have got away with this .
I have contacted trading standards and I emplore anyone who has a complaint about this company to do similar through the consumer advice service. If you require further info please send a private message .


Hi I’d be very interested in learning how you did this as we have a similar problem with Safestyle, I hope you see this message and thanks.

Lesley says:
10 February 2016

i am interested in what you say Ambrose as we currently have problem with Zenith going on for last 2 years with numerous fitting attempts and now they trying to take us to court to pay the second £6k, which we not happy about as each time they come there are more different problems and now not even convinced units are gas filled or are the right glass. how do we get that checked please so we can prove our case?

Nick Dardalis says:
23 February 2015

[Hi Nick, this comment has been removed. I’m sorry to say, Which? does not allow promotional activity from other companies. This is so we can maintain our independence. All the best, Mods]

james says: