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uPVC vs wooden windows

When it comes to uPVC vs wooden windows, this is not the first article written, nor will it be the last… But given most of us will have to replace a window or two in our lifetime, it’s important one can understand the important facts to ensure you can make best decision on what is a not insignificant expense… This article aims to highlight the pros and cons of both materials and weigh up what makes most sense. Enjoy!


Are wooden windows better than uPVC?

Are wooden windows better than uPVC?

The history of uPVC Windows

The late 1980s saw the popularisation of uPVC window frames due to the perceived benefits of this modern material. Unlike conventional plastic, uPVC was more rigid, less bendable, and crucially quite stable, especially when compared to organic materials like wood. Coupled with the introduction of double glazing, uPVC windows seemed to represent a modern, high quality and low maintenance choice vs. the traditional and often expensive wooden window option.

What is uPVC?

uPVC is short for Unplasticized Polyvinyl Chloride and it is manufactured by running sodium chloride through electrolysis, producing chlorine gas. Natural gas or petroleum is then used for making ethylene, which puts together ethylene, chlorine, and liquid vinyl chlorine.

uPVC properties

uPVC properties

We have already referenced some of the properties of uPVC that made it seem such a compelling material for application in window frames and even doors when launched in the 1980s:

Cheap: There is not getting away from the fact that uPVC window frames are possible to mass produce and therefore drive down the cost of manufacturing. Compared with bespoke timber framed windows uPVC can seem like a significant cost saving, although it is necessary to look at the full life cost – something we will refer to again later in the article.

Low maintenance: uPVC was introduced into the market as a wonder product that required little to no maintenance, which is an attractive proposition when faced with the alternative of timber windows, particularly with the paintwork which is prone to flake off over time. uPVC window frames do have their own issues however which are important to reference here.

  • Structural integrity – even though uPVC is relatively durable, their light weight means that they’re prone to sagging. Essentially the weight of the glazing can cause the frame to bend, an issue not seen with wood or aluminium window frames
  • Discoloration – over time uPVC window frames will discolour and peel. This is due to extensive UV exposure with the frames turning an unsightly yellow colour. Unlike timber frames which can be re-painted the same cannot be said with uPVC. If you’re looking to smarten up your house, you have little alternative other than replacing your windows.

Durability: One of the key selling points of uPVC window frames is claimed durability – probably the most important factor when deciding what type of window frames you go with. Compared to soft wood timber frames uPVC undoubtedly has a clear advantage here, but as we know different types of wood have different properties and we must be careful not to lump them all together. What is the best way of establishing how durable a product really is? Well, looking to see what the manufacturer warranty or guarantee offered is a good place to start. You will struggle to find a uPVC window maker that offer a warranty of more than 10 years on the uPVC elements of the window. There are plenty examples of uPVC windows that have lasted longer than 10 years, but it gives you an insight into how long they expect their product to last. By contrast, the best performing wood brands such as Accoya wood have been offering warranties of up to 50 years on their product.


This is always going to be a subjective point, but this article would be incomplete if we didn’t mention it. It needs to be said that uPVC window frames do look a bit….plastic. There is reason why conservation areas across the UK often do not allow uPVC frames, and it’s because of how they look. Where you have Victorian, Edwardian or other period housing stock, uPVC does tend to look out of place. There have been attempts in recent years with innovation to make uPVC look more like wood, but it’s proven very hard to achieve the natural biophilic look and feel that is achieved with real wood.


It’s easy to be dismissive of uPVC window frames. They have only moderate durability, discolour to an unsavoury patchy yellow colour, and don’t always look the part, but on the other hand they do represent good value for money, especially if you’re only looking to live in the home for approximately 10 years. Having to replace your windows twice starts to become quite expensive, so you really need to decide how long you’re planning to stick around… Bear in mind that having windows that are in a good state of repair can materially affect your house price, so it might not be someone else’s problem after all…

The history of wooden window frames

The history of wooden window frames

Whilst it was the Romans that pioneered the use of glass for windows, wood has long been the preferred choice of material for window frames. The size of one’s window through history has often represented wealth and class, and as window making techniques evolved, so the size of windows has increased. In the seventeenth century the fashion became to have taller, rather than wide windows, and to facilitate this they were often divided into four. In the same century the sash window was invented with the top sash fixed and the bottom sash sliding upwards.

In term of the species of wood used, oak and pine were the two most common, with oak offering better durability than the softwood pine.

Wooden window properties

Wooden window properties

Wood is a natural product which affords both positive and negative attributes. Below is list of considerations to be made aware of before selecting timber window frames:

  • The look. In contrast to uPVC, nothing beats the elegance and natural look of wooden window frames. The frames add character to a building, especially a period property and each window is one of a kind.
  • In the UK we typically paint our windows. This has two benefits – it improves the aesthetic and it protects the wood, meaning the windows last longer. However wood has a propensity to shrink and swell as the seasons change. This movement puts stress on the paint coating, and over time the paint will crack and ultimately flake off. This can look untidy and also let water into the window frame causing decay over the long term
  • Thermal Conductivity. Wood is a terrible conductor of heat, which means it’s a great insulator and will keep the heat and the cold out depending on the season. If thermal conductivity wasn’t enough, wood is also a good acoustic insulator and has proven to be better than uPVC and aluminium at blocking out sounds.
  • Cost. Wooden window frames are never the cheap option. Although some softwood window frames can compete on price with the likes of uPVC, higher end wood species and modified wood brands such as Accoya do come at a higher cost. What drives the relative high cost of wooden window frames however is the labour. Typically it takes approximately 17 man hours to make a timber window frame due to bespoke dimensions and crafting of the wood needed to achieve the required product.
Limitations of wood

Limitations of wood

The very thing that makes wood so good to look at and to touch, is also part of its inherent limitation as a building material… Wood is a natural, organic material which over time and subject to certain conditions like rain will decay or rot. However, whereas all uPVC broadly has the same properties and performance, wood covers a huge spectrum of performance from the cheapest low performance softwood, all the way through more robust hardwoods, and to the pinnacle of high performance and durability – acetylated wood, otherwise known as Accoya. Like we discussed on uPVC, you really need to determine how long you expect to be living in your house… Cheaper softwood window frames might last 7-10 years, slightly worse than uPVC, whereas a hardwood window frame (such as iroko, sapele, or even oak) could be expected to last anywhere from 10-30 years. This would depend on the exposure of the window (to sun and rain), the climate, or even the quality of the wood, which can vary batch to batch. For the belt and braces approach, an Accoya window frame is warranted for 50 years, with an expected service life from between 77-90 years, according to a recent study by the Heriot-Watt University in Edinburgh.


Replacing a window is an expensive exercise however when you look at it replacing the same window twice in a lifetime is not just doubly expensive, but also unnecessary. If you pick the right material, you can have the confidence that the window will be doing its job long after you’ve gone… Never has the adage ‘you get what you pay for’ been more true when applied to buying window frames, so make sure you spend the time to research what you need. Go and speak to your local joiner about what they would recommend, and don’t rush into buying a uPVC window just because it looks a bit cheaper – it’s probably a false economy…

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