/ 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?


Most large and medium sized double glazing installers have salesman commission to pay. The fitters are normally on price work so are always under pressure to finish a job quickly. Even though they may arrive in the companys vehicles and uniform, the van are normally rented to the fitters and uniforms given to them as part of the illusion. They are usually self-employed price worker deceiving not just the customer but also the Inland Revenue There are strict guidelines and rules allowing individuals to be self-employed as opposed to employed.
So even if the fitters have undergone some form of basic training usually in house they are unlikely to be able to afford or be willing to spend as much time on an installation as is required to do a good job even if they are capable

This comment was removed at the request of the user

Te Tucker says:
18 December 2016

We had a number of windows and doors from Anglian over a decade ago; several were not sealed properly so wind and in one case a lot of rain came in from above and below the frames, and since shortly after the 10 year guarantee expired, three of those units have blown. In view of that, for the next tranche of work (sold to us in August with advertised 6 week completion, but only fitted mid November), we went with Everest. Two of these units seem fine but the third has been a nightmare – glass scratched on the inside, door wouldn’t close unless the central stanchion (it’s a patio door to a balcony) was pushed in from the outside (!), and rain came through the ceiling of the room below it, plus lesser things like creaking, chipped handle, and even a key that broke in the hands of a fitter… Stopping the cheque has been effective in getting them back for remedial work – three times to date. In my view these companies are making a big mistake forcing the fitters to be pseudo self-employed – there is no real health and safety for them (despite what salesmen and surveyors say), they are not paid travel time yet are required to travel far and wide to jobs, and at the end of the day the quality of the products and the company’s reputation depends solidly on them. We won’t use either of these supposedly ‘good’ companies again. A friend tells me that double-glazed units in Holland are expected to last at least 20 years; why are ours such shoddy quality?

I had Everest fit several windows, patio doors & front door 2 years ago. I have since had nearly 40 visits to try & fix leaking, scratched windows, draughty patio door & lock kept ‘springing’ open, so house not secured & squeaky front door whose covers keep ‘dropping off’. We now have a one- centimetre gap around the patio doors, through which I can see into garden. This must be about 40 visits in 2 years & installation manager told me he wasn’t paid to listen to me going on about when am I going to get what I paid for? Not interested that I have been lied to several times.
HOWEVER, we had to pay 1/3 deposit £4,000 up front & sign credit agreement before they would do the first installation. They were in a panic, when I had made mistake on deposit cheque, came out straightaway.
GGF want £750+ to do a survey & I contacted an independent glass surveyor recommended by Which & his costs would be approx £1,000 & not admissible in small claims court!!! The whole system is skewed in favour of companies, who couldn’t care less Once they have your money, and against consumer rights. GGF was set up by Everest – conflict of interest? Now going to media- only avenue open once Everest have taken all my pension pot!

Do not use Anglian Windows ,we recently spent 2o thousand pounds on wiindows and doors taking 5 and a half days to install. They were so bad that it took two fitters 5 days to correct the work.The finish is not good but at least the voids around the windows and gaps have been fixed. Every window and door required some attention. The problems were so basic that it seems unreal that any fitting could be that bad.We have had to cancel the planed conservatory with the same company as I do not want them on site , this may mean them demanding 30% of the total cost of another 20 grand which we will of course fight. Please read disatisfied customer reviews on facebook as anglia windows has its own group they are so numerous.

Jacob Tobias says:
10 October 2018

The best advice I can give after 25 years of manufacturing aluminium glazing is “use your local companies rather than National” they will deliver what they promise and at a better price with much better service. [This comment has been edited to comply with our community guidelines. Thanks, mods.]