Choosing to install new sash windows is a big decision for any homeowner. With the rise in popularity of uPVC windows, many naturally think of this material when considering a replacement. uPVC sash windows might be similar to timber sash windows in terms of the operation and design.

However, the appearance is in many ways strikingly different and it will be clear that you have replaced your windows with a more modern alternative. This isn’t the most aesthetically pleasing choice you can make, especially where older properties are concerned.

For most homeowners who have older Victorian or Edwardian-style properties, aesthetics are important. Bespoke timber sash windows will be a better fit for your property in terms of appearance, and they can be made to match existing windows. In London especially, there can be stringent planning rules in place that dictate the style and appearance of windows, so changing to uPVC simply wouldn’t be an option. uPVC is far better suited to modern casement windows that are fitted into newbuilds and 20th Century properties.

What are the specific problems with uPVC sash windows?

Here are some specific examples of the problems you might find with uPVC sash windows:

  • There could be planning restrictions. Many of the older properties that are fitted with sash windows in London will be within conservation areas, which means any windows and doors must be replaced with similar ones. According to Architecture for London, around 1,000 of the 10,000 conservation areas in the UK lie within Greater London. There are 27 conservation areas in the City of London alone!
    If you live in one of these London conservation areas, you will usually need to replace doors and windows with like for like products, meaning that uPVC won’t be an acceptable option. It’s always advisable to understand all regulations before you plan any work. The Planning Portal gives the following advice: “If your house is in a designated area (conservation area, national park, area of outstanding natural beauty) there may be additional restrictions in place. In all these cases, you are strongly advised to check with your local planning authority before carrying out any work.”
  • uPVC didn’t exist in Victorian times… Sash windows became popular in the Georgian period and appeared in various guises until the 1930s, taking on different design features through the ages. Properties from these periods are distinctive in their appearance and may retain original features, including Georgian and Victorian window boxes. uPVC can look very out of place when fitted into a period property and could draw attention to your home for all the wrong reasons. In our experience, house-proud homeowners stick to traditional timber windows that are guaranteed to perfectly complement their properties.
  • Poor installation is a major issue. Since the uPVC boom of the 1970s, windows have become big business. Many new window companies have sprung up and it can be difficult for homeowners to know which ones to use. As uPVC is a material more commonly associated with newer properties, the companies offering uPVC windows may not have the experience required to install sash windows in your beloved period home. Ill-fitting uPVC windows might let in draughts, compromise energy efficiency and become a security risk. Timber windows can be made to measure by carpenters, specifically for your period home, so they offer a more tailored fit.
  • Frames may begin to go yellow over time. uPVC isn’t painted like timber and it can start to turn yellow, instantly ageing the windows in appearance. This is due to UV exposure, which will add to discolouration over the years. Timber windows will also experience some wear and tear, but maintenance is far easier as they can be painted over. It’s difficult to keep uPVC windows looking new and when they begin to show their age, they often need to be replaced entirely.
  • There’s less choice in terms of appearance. A uPVC window will look like, well, a uPVC window. There are limited options when choosing the colour of the frame, as uPVC isn’t painted. Timber allows you to choose the colour of the paint, which means you can match it to doors, existing windows and masonry, or select the paint colour you have always wanted. Keep up with home design trends and redesign your home around modern living, whilst retaining the traditional charm of a sash window.
  • It’s difficult to replace a single window. One of the issues with a uPVC sash window is that it will stand out. This isn’t something you want amongst older sash windows that have a timber boxframe; it will be immediately obvious which window has been replaced. To maintain consistency, you would need to install uPVC windows everywhere, even if only one window actually needs replacing. Timber windows will be individually made for your property, allowing you to replace or maintain them as required without having to change the appearance.
  • General maintenance can be challenging. It’s much harder to repair uPVC in the same way as timber – you may be able to replace glass or make some simple repairs to the uPVC itself, but bigger repairs will often require a full window replacement. This can make uPVC a false economy; windows might cost less in the first place, but they can easily cost you more over time. With timber, you have the option of replacing individual parts or repairing chips and scratches. A carpenter will be able to make new parts, from a new sill or sash bead, right through to a whole new sash that can be fitted into the existing box frame. By repairing and maintaining your sashes, you can get a longer lifespan out of your window


uPVC sash windows vs bespoke timber windows – let the experts help you choose

We are here to make the sash window selection process easier for you. Our team offer a consultative process, working to craft sash windows that are as unique as your property. Every window is custom made, so it will be the perfect design and style for you. We can make sash windows that will fit in with existing windows or make something unique for you. This is the real selling point of handmade timber sash windows; they will be everything you want them to be.

If you would like to ask any questions about timber or uPVC sash windows, the similarities, the differences and what will be right for your home, we are happy to help. You can call us on 020 3930 1379, email or fill in our contact form.

Contact the Wandsworth Sash Windows team

Talk to us – we can help with your bespoke window, door and joinery requirements. Call 02079247303 or email