How much one double glazed window costs is based on a few factors. If you just want to buy the window to install yourself, it will cost less than if you want an installer to fit it for you.
If you want to simply buy one double glazed window without installation it could cost anywhere between £100-£300. That’s for a simple casement window, but other types like sash or tilt and turn windows could cost more.
It’s recommended that you get a reputable installer to fit your double glazed windows because they’ve had the relevant training and will be able to install it much more quickly. How much it will cost for them to install one double glazed window will very based on your location, the type of window, how difficult the window is to access and whether you choose standard white uPVC or a coloured or woodgrain effect. An average uPVC casement window might cost somewhere between £300-£400, while a dual turn window might cost between £550-£660 to install.
Do you really need to replace the entire window? If it’s just the double glazing that needs replacing, for example if it’s misted up inside, this will cost much less. Most window installers or a glazier will be able to just replace the sealed unit inside, and that may cost as little as £250. It’s always best to get a range of quotes from reputable companies so you know you’ve got a great price and you’re sure you’ll get excellent service.