Best double glazing companies Double glazing prices

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Don't pay over the odds for your windows - check average prices in our tables

More than 40% of Which? members say it’s difficult to find good advice on double glazing, and a quarter had no idea initially how much double glazing should cost, so we’ve produced a pricing guide to help you separate the good value quotes from the bad. 

We asked 15 recommended double glazing companies from Which? Local to tell us the typical prices they would charge for common double glazing jobs. The prices were collected in 2012 as part of our last investigation into double glazing services. As prices change over time, we are currently collecting updated pricing information for 2016, which we'll publish on this page later this spring.

There are plenty of variables that affect prices (see ‘Cost of extras’ below for examples) and every house is different – but these prices should give a rough idea of what to expect to pay.

The tables below show how much you should expect to pay for various double glazing jobs, from different sizes of sash and casement windows to replacing all the windows in a house. 

Only logged-in Which? members can view the results in the table below. If you're not yet a member, try Which? for £1 to get instant access. 

Casement uPVC windows cost
Size (mm)Price
600 x 900
600 x 1200
1200 x 1200
1200 x 1800
Small terraced house (six windows)
Semi-detached house (eight windows)
Large detached house (12 windows)
Sash uPVC windows cost
Size (mm)Price
600 x 900
1200 x 1200
1100 x 1300
1000 x 1500
Small terraced house (six windows)
Semi-detached house (10 windows)
Large detached house (17 windows)
uPVC door cost
Size (mm)Price
900 x 2100


How we calculated our double glazing prices

Typical prices - The price range shown for each scenario covers the middle 50% of prices collected from 15 Which? Local traders in 2012. The quoted prices are final (including all discounts) for standard white uPVC frames with B-rated glass and include materials, labour, removal and disposal of existing windows, internal and external ‘making good’, VAT and incidentals.

DG sash window

uPVC sash windows tend to cost more than casement

House sizes - The examples are based on the following number of windows and sizes (mm): Casement windows – Small terraced house – 600x900 (x1), 900x1200 (x1), 1200x1200 (x4); Semi-detached house – 900x1200 (x2), 1200x1200 (x4), 1800x1200 (x2); Large detached house – 900x1200 (x2), 1200x1200 (x5), 1800x1200 (x5). Sash windows – Small terraced house 600x900 (x1), 900x1200 (x1), 1200x1200 (x4); Semidetached house – 900x1200 (x2), 1200x 1200 (x4), 900x1200 (x4); Large detached house – 900x1200 (x2), 1200x1200 (x5), 900x1200 (x10)

Cost of extras

There are plenty of style and design options to choose from on double-glazed windows, all affecting the price you pay. Common extras/variations include:

  • Wood effect uPVC frames – cost around 15-20% more than plain white frames.
  • Aluminium frames – cost around 30-50% more than white uPVC frames.
  • A-rated glass instead of B-rated – adds up to 10% to the cost.
  • Higher windows – all traders we asked said they wouldn’t charge extra to install windows on the first floor level, but windows on the second floor or higher may incur extra costs.

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