Which? reveals best double glazing companiesAnglian, Everest, Safestyle and independents rated

13 October 2016

Cat looking out of double glazed window

The bottom-rated double glazing company came 30 percentage points behind the top

Our survey of more than 2,000 double glazing customers has revealed a big difference between the best and the worst double glazing companies.

We asked the customers of independent double glazing firms plus big brands Anglian, Everest and Safestyle to tell us about their experience of buying double glazing. The results may surprise you.

After crunching the data, we calculated a customer score for each double glazing company in our survey - this allows you to easily compare them to see which is the best. We discovered that the top-rated company achieved an impressive customer satisfaction score of 86%.

By contrast, the double glazing company at the bottom of the table scored just 56%. This is 30 percentage points lower than the top-scorer. 

To find out who took the top spot, and who was left far behind, read our double glazing reviews.

Best double glazing companies

We calculate a customer score for each double glazing company in our survey. This allows you to easily compare the companies.

Our customer score combines how satisfied people are with the double glazing company and whether they would recommend it to a friend. 

To dig deeper into each double glazing company, we also asked customers to rate a number of sales and installation factors. That includes quality of products and installation, customer service, value for money, knowledge of staff, and mess during and after the installation.

The highest-scoring company was rated as 'excellent' for all but one element, after sales support. Even then, it was still rated as 'good'. 

But where it really stood head and shoulders above its rivals was for value for money, customer service and how well the installers communicated. The other double glazing companies scored 'fair' or 'poor', whereas our top-scorer was 'excellent'.

Buying double glazing

The majority of people we asked (53%) said the reason they chose the company they used was because the salesperson didn’t make them feel pressurised. 

We've heard of instances where a salesperson quotes a high price at the start, but drops it dramatically during the course of a visit. Don’t let this persuade you to sign a contract there and then.

Instead, aim to get three quotes (35% of people we surveyed only got one) so you get a fair price and have some time to think. Ask that each quote includes details of all products, materials, work and costs, as well as optional extras, so you can easily compare them.

Choose an installer that’s registered with a Competent Persons Scheme, such as Fensa, as it means they can self-certify that their work complies with building regulations.

Find out what sales tactics you should expect - read our full guide to double glazing sales and quotes.

(Online survey: August 2016. We asked 2,239 Which? members who had double glazed windows/doors installed in the past five years about their experiences.)

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