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Why get double glazing?

  • Save up to £195 per year on energy bills
  • Improve your property's value
  • Reduce outside noise

London sash windows cost

  • The average price of a new uPVC sash window in London is around £700-£800
  • Repairs of wooden sash windows can cost from £20 to more than £500
  • uPVC sash windows might be a more suitable option
  • Get quotes from at least three window installation companies in and around London

Sash windows are a popular choice for many homeowners, and this is especially true in London’s traditional Victorian, Edwardian and Georgian homes. 

Replacing old wooden sash windows with double glazed uPVC sash windows allows those living in a traditional Victorian, Edwardian and Georgian home to help preserve the character and elegance of your home. It will also enable you to overcome issues associated with their timber counterparts, such as draughts and poor security. 

If your windows are draughty, however, paying the costs of double glazing could be something to consider as well. 

If you’ve yet to figure out whether sash windows are the right investment for you, you can use this guide to help. We go into full detail on the costs involved, as well as the pros and cons of installing them and any alternatives available. 

If you’ve already done the research, however, and you’re ready to find suppliers, fill in this form to receive free, tailored quotes. 

Sash windows on a traditional home

What are the common problems with traditional wooden sash windows?

Like most things, there are some challenges, especially with traditional wood sash windows. These include: 

  • They let in the cold – Traditional sash windows have a 3mm gap between the sashes and frame to allow the glass panes to open smoothly. Unfortunately, this design lets in draughts. Most traditional sash windows are also single glazed, so aren’t as efficient as keeping the heat inside your home compared to double glazing. 
  • Noise can be let in – Due to its 3mm gap, traditional sash windows could let in more noise. This is not ideal when you live in London, a city that currently has almost 10 million habitants. 
  • Maintenance requirements can be high – Traditional sash windows are made of wood, and this means they can be high maintenance. The frames not only have to be painted, sanded and varnished regularly, but they will eventually split or flake. In the harsh British weather, they can also rot. The good news is that with proper maintenance, this can be avoided. 
  • They might not be totally secure –  Most traditional sash windows are single glazed, which means they are a lot easier to break as they are not reinforced. In addition to this, it’s unlikely they’ll have modern security measures, like locks. They are also prone to warping due to Britain’s varying weather conditions. 
  • They’re dusty – That darn gap again – dust and first will come through it, especially when it’s windy, and if you’re really unlikely, so will rain.

Is it worth repairing sash windows?

Yes, as long as the repairs are carried out properly. Carrying out high quality repairs can extend the life of your traditional sash windows by decades and improve the comfort of your home. It’s worth adding that if you keep your traditional sash windows, they will require regular maintenance. 

But if you’re willing to put the time and effort into caring for them, then paying for small repair work every now and then will be a lot cheaper than completely replacing your windows. 

However, in today’s day and age, not everyone has the time to maintain their windows. If this is the case, it might be worth replacing them with low maintenance uPVC sash windows. Ultimately, it’s down to you, your lifestyle and your disposable income. Consider a pros and cons list about whether the financial investment outweighs your time. 

To give you a rough idea of the repair costs on traditional sash windows, check out the table below: 

The costs to consider with repairing sash windows

Sash window repairs will be affected by factors, such as: 

  • The size of the window
  • The condition of the window and how much work is required
  • How easy the window is to access
  • Whether the window is made from softwood or hardwood
  • Whether the work is being done on an upper or lower sash

If you’re unsure about wooden sash windows, uPVC ones might be a more suitable option. If you live in London, they can negate all the issues we’ve already mentioned. But here’s a bit more detail anyway: 

  • Good insulators – uPVC windows provide excellent insulation, meaning heat will stay inside your home. This will help keep your energy bills lower because heating won’t be as required as often. In fact, the Energy Saving Trust estimates that installing A+ rated double glazing can save you over £100 per year. 
  • Cut out noise – Thanks to its strong insulating properties, unwanted noise from outside is also blocked out. This is ideal when you live in London and you have to contend with traffic, parties and people 24/7. 
  • Low maintenance – As mentioned above, uPVC sash windows are low maintenance. They don’t decay, rust or peel, and they’re unaffected by extreme weather or pollutants. You will need to wipe them clean on occasion though. 
  • Value for money – uPVC is the cheapest type of window frame material and can be half the price of timber windows. 
  • Durability – uPVC is very strong and should last you between 20 and 35 years. 
  • Versatility – uPVC is available in several colours and styles. White is the standard colour, but you can have grey, blue and green, too. There’s also woodgrain effect uPVC, in finishes like oak, cedar and mahogany. These mimic both the appearance of wood, but it’s texture too, preserving your home’s character. 

Like most things, however, there are drawbacks to uPVC: 

  • Costly – While they offer good value for money overall, there is quite the investment. You’re looking at approximately £800 per window depending on the type of uPVC window you choose. This means that if you need eight windows, you’re looking at an investment of £6,400, which is a lot off the bat. Look below for more detailed costs on average. 
  • Needs more research – There’s quite a bit of research involved before you install uPVC windows. This is because there’s a lot more choice available before you reach the installation stage. You also need to research different installers, get windows surveyed and sign paperwork, etc before you get the final product. 

The average cost of a uPVC window in London is around £700 to £800, but this will be affected by a number of factors, including: 

  • The size of the window – The larger a uPVC sash window, the more it will cost
  • The type of glass you choose – Decorative or stained glass will cost more than clear glass
  • The colour and finish of the window frames – Coloured or woodgrain effect uPVC will cost around 10-to-15% more than standard white uPVC
  • The type of locks and window furniture you choose – Opting for extra secure window locks, such as opening restrictors and multi-bolt locks, will increase the price of your window. Choosing chrome, brass or gold window handles instead of standard uPVC ones will also push up the price
  • The energy efficiency of the window – New uPVC sash windows typically range in energy efficiency from B to A++, which is the most expensive, but the best

If you’d like to find out what you might spend on double glazing, which most uPVC sash windows have, our guide on double glazing costs has everything you’ll need to expand your knowledge. 

Alternatively, the table below shows you the average cost of different sized uPVC sash windows in a white and woodgrain effect finish. 

The cost of uPVC sash windows in London

Alternatives

It can be hard getting planning permission for uPVC sash windows, as there can be tough restrictions in place. This includes if they don’t match the historic character of your property or the surrounding area. On top of this, it’d be unlikely you’ll be able to upgrade your double glazing, too (if you don’t already have it). 

In these circumstances, you’ll be advised to either repair your existing wooden sash windows or carry out a like-for-like replacement of your timber sash windows. If you want to improve your windows’ energy efficiency, however, you could consider secondary glazing. 

This involves adding an extra pane of glass or plastic onto your existing windows to improve their heat and noise insulation. Unlike double glazing, which would remove a single glazed window and replace it, secondary glazing is simply added to the existing window. 

If you’re ready to consider alternatives to your current windows, fill in this form and we’ll be in touch with free quotes. 

How do I get quotes?

We recommend getting quotes from at least three window installation companies in and around London. Some companies outside London will cover the area. This will give you a strong overview of what you’ll be paying and allow you to make the right decision. After this, check Trustpilot or Google for customer reviews before making your final decision. 

While some will offer a quote online, installers should visit your home to assess how any work will affect your property and its structural integrity and appearance. They should then arrange a consultation with you to discuss the type of sash window best suits your property. All quotes should be sent to you via email and be itemised. 

If you’re time poor and want our help, fill in this form to receive free, tailored quotes. We’ll pair you with companies registered by one of the government’s competent person schemes: FENSA or CERTASS. This means you’ll work with fully vetted and assessed companies so you can rest assured that any work will be of a high standard. 

Summary

  • Traditional sash windows have a 3mm gap between the sashes and frame to allow the glass panes to open smoothly, which lets in draughts.
  • Carrying out high quality repairs can extend the life of your traditional sash windows by decades and improve the comfort of your home.
  • uPVC windows provide excellent insulation, meaning heat will stay inside your home.
  • The average cost of a uPVC window in London is around £700 to £800.
  • It can be hard getting planning permission for uPVC sash windows, as there can be tough restrictions in place. 
Written by:
Max joined The Eco Experts as content manager in February 2024. He has written about sustainability issues across numerous industries, including maritime, supply chain, finance, mining and retail. He has also written for  City AM, The Morning Star and the Daily Express.
Reviewed by:
Tamara Birch, senior writer, The Eco Experts
Tamara has written about environmental topics for more than four years. This includes advising small business owners on cost-effective ways, like solar panels and energy-efficient products to help them become more sustainable. 
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