How to buy double glazing Double glazing sales and quotes

Window pane

How much does double glazing cost?

Double glazing salespeople often have a dubious reputation. Here we explain how to get the best quote, and steer clear of the tricks that some double glazing companies use.

Meanwhile, our double glazing satisfaction survey reveals the best and worst double glazing companies, according to customers' experiences.

Sales tactics

A Which? investigation found that double glazing salespeople frequently quote a higher price to begin with, which they drop over the course of their sales visit. The price your quoted could drop by 75%, or over £10,000, during a sales pitch.

You should also avoid signing up to a double glazing contract on the spot.

Double glazing prices

A quarter of Which? members said they initially had no idea how much double glazing should cost. To find out how much you should expect to pay for various double glazing jobs, from sash windows to doors, see our double glazing pricing guide.

Double glazing grants

There aren't any grants available to help you pay for double glazing. Some members of the double glazing industry have been campaigning for a scrappage scheme, similar to the car scrappage scheme, but to date any scrappage discounts offered by window companies are their own special offers.

However, there are grants available for other energy-saving home improvements. If you're thinking of installing solid or cavity wall insulation or loft insulation, it’s worth checking whether an energy grant is available to help cover the cost. 

Our energy grants guide has everything you need to know, including how much money you could be eligible for and how to apply. 

Window fitter

Use Which? Local to find a recommended glazier

Find a reputable double glazing company

Here are some tips on how to find a glazier:

  • Ask friends and neighbours for recommendations. 38% of Which? members have used a company that was recommended by a friend or family member.
  • Get at least three quotes. While a third of Which? members got three quotes before deciding on the company they used, worryingly 31% only got one quote.
  • Compare the products as much as possible like-for-like. Compare the costs of what is included as standard, and
    what is costed separately as optional upgrades or extras.
  • Ask the companies for addresses of properties you can visit to look at some installations. 
  • Don’t pay a big deposit, and don’t sign up on the spot. Be wary of a company that starts off with a high price then
    dramatically drops it. Take your time to compare quotes.
  • Go for a recommended company which has a record of good customer service – if you have a problem they are more likely to rectify it.
  • Look for companies that have been around for more than 10 years.

Which? members can also find 1,000 recommended double glazing installers using Which? Local. If you've encountered a good double glazing company, you can also make a recommendation using the site.

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