Windows Archives - Dempsey Dyer
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UPVC, aluminium and timber manufacturers

Operating since 1977

Full range of Deceuninck, Reynaers and Accoya systems

Manufactured in the UK

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The Variety of Timber Casement Windows from Dempsey Dyer

Over the years, the casement window has become the standard window fixture, particularly in the last 20 years since uPVC took over the market. uPVC entered the market due to the lack of longevity that timber provided to homes back in the 1970s through to the 1990s. However, since the early 2000s, modern design innovations and technologies have allowed resins to be developed that allow for timber installations to make a return to modern UK homes without having to worry about rotting, warping or discolouration. As such, here at Dempsey Dyer, we have developed a range of timber casement windows that provide the home with the best in thermal efficiency, security and weather protection. uPVC still remains an excellent option for homeowners, but timber has finally made its full comeback to wonderful effect. 

Today we wanted to focus on the three variants of our timber casement windows that we provide to trade installers and to homeowners: Flush Sash, Mock Sash and Stormproof Casement. Each window has something slightly different to offer the UK home. All of them have excellent properties in retaining warmth in the home, providing exceptional and modern levels of security and protection from weather damage. 

Flush Sash

Our timber flush sash windows have the professional touch that homeowners of heritage properties are looking for. Since uPVC entered the market, we have seen modern homes built with uPVC double glazing and homes built in the 1970s and later having their single glazed windows upgraded to uPVC. However, there has been a spot missing for the heritage home that has no interest in providing the home with modern uPVC finishes. Fortunately, modern timber casement windows have arrived to fill this gap in the market! 

Flush sash windows are stylish and discreet due to their flush design against the wall. They provide the traditional home with a modern upgrade that holds true to their classical style. They also provide the modern home with a touch of grace that may be missing if they had their uPVC windows installed sometime ago!

All of our timber casement windows provide homes with exceptional thermal efficiency. In these modern times when energy prices are skyrocketing with no sign of slowing down, it has never been more important to ensure that the energy we are using is used to its best effect so that we’re not wasting our money on leaking heat! 

Mock Sash

The mock sash timber casement window provides the same visual effect as the flush sash casement window but uses modern opening and closing methods. From the outside, you wouldn’t know that this window actually opens and closes like a modern casement window as it looks identical to traditional timber sash styles. However, the homeowner can enjoy modern window design from the inside. If you’re looking to give your home the contemporary upgrade without sacrificing on the outward appearance of the home, then look no further than the mock sash timber casement window! 

Like with all of our timber casement windows, the mock sash provides exceptional safety using our top of the line high security locking system. With a modern timber casement window from Dempsey Dyer, you can ensure that your home is protected from potential intruders. It used to be that timber windows were inadequate security measures to the ease with which intruders could break through them after they had rotted or degraded through the weather over several years. However, due to the modern application of resins, we can assure you that your timber casement window will not degrade through the weather at all! 

Stormproof Casement

Our stormproof timber casement range provides the home with the absolute best in weather protection. These windows come in a vast range of styles, including the two mentioned previously, so that you can customise your windows to your exact specifications. Whether you’re looking to provide the home with a traditional sash style or something more modern, our stormproof timber casement windows will give your home all the weather protection it needs without any signs of degradation.

Modern Timber Casement Windows from Dempsey Dyer

Our timber casement windows are available for trade customers and homeowners alike. Whether your client is looking for that modern upgrade to their heritage home or you yourself are looking to give your home a touch of the classics, then you’ll find what you need with Dempsey Dyer. All of our windows provide the best in thermal efficiency, security and weather protection, and all are customisable with a variety of timber species so that you can get the exact effect with the exact colour you’re looking for.

If you’re interested, please use our free online quoting engine today to get a quick price for your project! You can also contact us directly if you have any questions or call us on 01977 649641!

What Makes uPVC So Popular?

uPVC was first manufactured back in the 1930s, but it didn’t become one of the major manufacturing materials until the mid-1950s. Since then, almost every decade, uPVC has grown massively in popularity. It really took off during the 1980s in Britain when double glazing also became a standard in modern home installations. Since then, both uPVC and double glazing have become staples of the modern home. Older British homes that haven’t had uPVC or double glazing installed yet are renowned for leaking heat, resulting in colder homes during the winter and hotter homes during the summer. With the introduction of double glazing and uPVC back in the 1980s, homes that had previously been difficult to keep warm and were a threat of overusing gas and heating systems now had a way of insulating their homes and making sure that the heating they were spending their money on, wasn’t leaking out of poorly insulated installations, like outdated timber single glazing. So, why has uPVC remained popular to this day, 40 years later? After such a long time in use, it still remains the most widely used material in home renovations and installations. Here at Dempsey Dyer, we wanted to focus on the key benefits of uPVC and how it continues to improve homes across the country to this day.

Thermal Efficiency

As mentioned, thermal efficiency has always been one of the major positives of having uPVC installed in your home. Timber is a natural insulator, which is why it has been used for centuries as the main material for installations such as doors and windows. However, timber, if not treated properly, degrades significantly over time. This degradation can lead to those installations becoming inefficient over time. This isn’t the case these days with newly installed timber because of how the wood has been treated and manufactured. However, older installations have not had the proper treatment before installation and therefore struggle to maintain their thermal efficiency. Therefore, as uPVC can achieve the same level of thermal efficiency, it makes sense as a replacement for older timber installations. As Britain moved away from timber, it naturally moved towards uPVC for this reason.


uPVC also counteracts timber’s lack of longevity by being an incredibly durable and weather-resistant material. As it is synthetic, rain and wind do not have much of, if any, effect on the material. Timber naturally absorbs water unless coated properly and therefore can become rotten or mouldy relatively quickly. uPVC has no such issue. All it requires is a wipe down every so often to remove any deposits of dirt or grime to keep uPVC windows and doors clean and as good as new. As a result, uPVC has a relatively long lifespan compared to older wooden installations. With the promise of similar levels of thermal efficiency, combined with the longevity and low maintenance requirements, it is no wonder that uPVC was the best choice for new installations back in the 1980s.

Old timber doors and windows are also at greater risk of being broken into or broken through because of the natural degradation that starts to set in after so many years. uPVC offered homes a chance to modernise the locking systems of the various openings to the outside. Multi-locking systems around the frames enable doors and windows to have much-increased levels of security across the board. 

Low-Price Point

However, its exceptionally low price point is uPVC’s greatest strength compared to timber, composite, and aluminium. uPVC offers equal levels of thermal efficiency, security and durability whilst also being incredibly cheap to produce. Installations made from uPVC are much cheaper than their timber and aluminium counterparts for this very reason. Furthermore, uPVC is fully recyclable, meaning that once the installation has reached the end of its natural lifespan, the material is melted down and reshaped into something new! The combination of its recyclability and its low price point gives uPVC modern benefits when compared to modern uses of timber and aluminium. Timber has had a resurgence in its usage because the drawbacks of older installations have been negated with modern coating and manufacturing processes. However, uPVC remains popular because of its low price point and recyclability.

uPVC from Dempsey Dyer

We provide uPVC products across the nation at Dempsey Dyer, from Southampton to Cowdenbeath. If you’re looking for your next uPVC product, why not get a quote from us today? Our easy to use online pricing tool can give you an accurate price within minutes. If you have any specific questions for us, please feel free to contact us using our online contact form, and one of our wonderful team members will get back to you as soon as possible.

We look forward to hearing from you!

uPVC Windows vs Aluminium Windows – Which is best for your customers?

Unplasticised Polyvinyl Chloride, otherwise known as uPVC, is a low maintenance alternative building material that can substitute for timber or aluminium. uPVC has become a popular choice for homeowners looking for effective thermal insulation and noise reduction and is considered a more cost-effective alternative to more traditional materials due to its lower initial price point. The material is made from vinyl polymer bound to chlorine atoms and boasts very high strength. uPVC is among the top three most popular (by usage) synthesised plastics in production worldwide!

Aluminium is a traditional, high-price point material for windows and doors. Aluminium has often been considered the best material for windows because of its longevity, durability, and providing a distinctive, high-quality look to a building. However, it has been criticised over the years for its poorer thermal performance compared to other materials, although this can be circumvented with modern innovations. As uPVC begins to take over as the most popular material on the market, is it time to say that uPVC is now the more attractive option. Or is aluminium still the ultimate choice?

Durability and Installation

uPVC windows are exceptionally durable for the low price point at installation. Highly resistant to wind and rain, uPVC is an incredibly strong material, proved by its popularity across many industries. Due to its composition, uPVC will not rust or rot and is resistant to chemical erosion. The overall low maintenance of uPVC is an incredibly important part of why they are so attractive to homeowners. The composition is designed to be a ‘fit and forget’ installation that does not require any special coating to ward off dirt, dust and bacteria.

On the other hand, aluminium has a much longer lifespan than the uPVC at around 45 years! Therefore, the higher price point of aluminium windows is reflected in them is a long-term investment for homeowners looking to increase the value of their homes. However, the low price point of uPVC means it could be a much more cost-effective solution for the modern homeowner.

Both uPVC and aluminium are lightweight materials that are easily manipulated. As a result, installation is considered an easy process with both materials. In terms of production, aluminium requires large amounts of energy for the binding process in creating the alloy. Therefore, whilst the installation process can be relatively simple, aluminium production is complex. uPVC, on the other hand, is very easily produced and sourced. As it is among the top three synthetic plastics, a consistent supply of uPVC is available for installations, which is reflected in its low price point.

Heat Insulation

Aluminium as a material has taken steps to become a better heat insulator. Through a thermal break, aluminium elements of the installation are separated to prevent global cooling of the whole installation. The material itself has been called a poor insulator, and homeowners may have cold window sills in the winter. However, the modern innovation of thermal breaks ensures that aluminium is a high-performance thermal insulator. uPVC, on the other hand, is an exceptional heat insulator. The material does not conduct heat, preventing temperature shifts over the year. Therefore, whilst also being a cheaper alternative to aluminium, the energy efficiency of uPVC is relatively the same, if not better. Homeowners can be sold on much lower energy costs over the course of the year due to not needing to regulate the temperatures of their homes with fans or heating with both uPVC and aluminium windows.

Aluminium has a sleeker and higher quality ‘look’ to it. Traditionally, aluminium has been considered the premium material when it comes to windows. The lower price point of uPVC, however, coupled with its various benefits, is extremely significant for potential customers compared to aluminium. When coupled with the potential for lower energy costs is similarly significant to potential customers, particularly as prices for a lot of materials and energy are currently going up.

Which is best?

There is no definitive answer when it comes to deciding which is better. Aluminium is more expensive but has a much longer life span and provides an ultra-modern aesthetic to the home, potentially raising its value. On the other hand, uPVC has a lower life span but is an exceptional thermal insulator requiring low maintenance with a much lower price point. 

Here at Dempsey Dyer, we offer both aluminium and uPVC windows in various styles and colours. Using our online quoting engine, you can design the window that you need in the material you desire to receive a free quote today! Furthermore, don’t hesitate to contact us with any specific questions or join our free newsletter to receive updates on everything happening here at Dempsey Dyer.

Signs You Need to Replace Timber Windows and Doors

What are the signs that you need to replace timber windows and doors? If you have wooden windows and doors in your home, then they might already be sending you signals that they might need changing. While these windows and doors have a fantastic, classic look, they do have plenty of drawbacks. Your timber windows and doors will need a lot of regular maintenance and upkeep, and even then they might need repairs after just a few years.

So, what are the signs you’re looking for? One of them could be whether your living space feels cold and uncomfortable, as your wooden windows and doors may be causing this. Another sign might be if condensation is building up on the window, and this could mean that the timber is starting to wear down. And, if your window frames are beginning to crack, twist or even discolour, then their age might be getting the best of them.

At Dempsey Dyer, we can help you replace timber windows and doors if you see any of the signs. We can offer high-quality timber windows for commercial clients, and we can help homeowners get new windows for their property as well. Our timber windows and doors are market-leading, and we use resilient Accoya wood for a high-quality finish. If you’re interested in replacing timber windows and doors, get in touch with us today!

Signs to Replace Timber Windows and Doors

Colder Living Space

If your living space is feeling cold or uncomfortable, then it could be a sign that your timber windows and doors are beginning to struggle. If you have older windows in your property, then they might have single-glazed glass which doesn’t offer a lot of insulation. And, while timber is a natural insulator, the material can begin to wear down over time. Because of this, gaps can emerge within the window and door frames that allow cold air and draughts to rush into your home.

As a result, you should check your timber windows and doors if your home feels cold without you relying on your central heating. Your window might have cracks in the wood, or the whole frame may have warped out of shape. Not only that, the single glazed glass may be struggling, and you could need replacement double glazing as well. Replacing your timber windows and doors, though, ensure that you can make your home warmer and more thermally efficient.

Condensed Panes

Another sign you may need to replace timber windows and doors is condensation. Condensation is a mist that builds up on the glass panels in your windows and doors when hot and cold air clash. Most glass units, including double glazed units, are designed to keep the hot air inside your home and the cold air outside it from colliding. So, when they do, it could be a sign that your timber windows and doors are beginning to wear down.

You should check your timber windows and doors for whether there are any gaps in the sealant. If the sealant in your glass panels has broken, then you’ll need to replace the glazing in your window or door at least. And, while condensation can build up on the inside and outside of your glazing, the best way to stop it is by getting new windows or doors altogether. When you do that, you can enjoy a more durable, weather-resistant window or door that doesn’t have issues with condensation.

Weather Damage

Over time, the signs you need to replace timber windows and doors only get bigger. And, after a while, the signs become too obvious to ignore. One of the main signs is weather damage, which is usually an accumulation of multiple years being exposed to poor weather conditions. Wooden windows and doors struggle in wind and rain, which can cause the timber in your profiles to crack, twist, and warp out of shape.

You should regularly check your timber windows and doors for weather damage, including cracks and gaps in the frame. And, if the profiles have warped out of shape, then you should look to reseal your windows or doors. However, you could replace your timber windows and doors with brand-new designs that have more resistant profiles. With Dempsey Dyer, you could pick uPVC, aluminium and even Accoya timber windows and doors that are much more comfortable in bad conditions.

Replace Timber Windows and Doors with Dempsey Dyer

Spot the signs you need to replace timber windows and doors in your home today with Dempsey Dyer. You can explore our site to see our full range of timber windows and doors, or you can contact our friendly team online. And, if you’re a commercial customer, then start your trade quote to help your customers find the best timber windows and doors to replace their old ones.

The History of Timber Windows and Doors

What is the history of timber windows and doors? While you might hear people talking about wooden windows and doors as being a ‘traditional’ option, you might not know why wooden windows and doors are the standard. It’s because, over the years, wood has been a reliable material for builders, architects and designers. Not only that, wood has been around and in use for several thousands of years, meaning the history of your windows goes much further back than you may know.

In this article, we’ll teach you about the history of timber windows and doors, and how that history has affected the modern designs you see today. Not only that, you’ll see the designs in a whole new light, and you’ll understand why features of timber windows and doors are the way they are. From there, we’ll see how modern wooden windows and doors are inspired by that history, but go in a new direction. As a result, you’ll get the full picture on timber windows and doors.

With Dempsey Dyer, you can get timber windows and doors that combine tradition and history with innovation and quality. Our timber windows and doors bring period style to your business’s product range, and they can also offer the high-end performance your customers need. Additionally, we can help homeowners find timber windows and doors for their properties, as well. If you’re interested, contact us today or start your trade quote.

History of Timber Windows and Doors

We know that the history of timber windows and doors stretch back thousands of years. In fact, the earliest windows initially appeared in Alexandria, in Egypt at the time of the Roman Empire, around 100AD. However, that’s only when the wooden window had glass added to it, which is when it became a design that we would recognise today. However, the glass that was used was thick and opaque, meaning you couldn’t see very well out of them!

Wooden windows and doors are first defined in the 13th Century, and originates from the Old Norse phrase for wind-eye. Further on, timber sash windows were developed in the Netherlands in the late 17th Century, and these frames were constructed in a similar way than they are today. Beyond that, construction of timber windows and doors evolved with different varieties of wood being uses. Oak was the initial choice, but later mahogany and imported softwoods became more popular.

As a result, the story of timber windows and doors is thousands of years old, and the story has been changed by people from all over the world. Features like sash windows, sash pulleys, box frames and cornices have come and gone, and some of them have stood the test of time. So, if you have old wooden windows and doors in your home, you now may be able to see more of where they came from and how they came to be. Now, though, we’ll see where modern timber windows and doors are today.

Modern Timber Windows and Doors

Modern timber windows and doors take the best of old designs and marry them with the technology of new windows. Inspired by modern uPVC and aluminium windows as much as timber designs, new wooden windows and doors are more durable and more efficient. As a result, you can benefit from improved thermal performance inside your home with new wooden windows and doors. You’ll get advanced double glazing and more resistant profiles that create better insulation for your property.

Another benefit of modern timber windows and doors includes the range of designs you can now choose. Nowadays, companies all over the UK are coming up with unique ways to bring classic timber windows into the modern day for your home. You can find timber sash windows with traditional styles and features, but combined with modern features like advanced multi-point locking systems. Because of this, modern timber windows and doors are as secure and strong as they are stylish.

Even the type of wood in timber windows and doors is still evolving today. You can now get engineered timber profiles, meaning that the timber has been cleverly modified to make it more weather-resistant, meaning wind and rain won’t cause the same level of damage. As a result, you don’t have to regularly maintain modern timber windows and doors like people have had to do throughout history. Because of this, you can enjoy them without much less effort.

Timber Windows and Doors Prices

At Dempsey Dyer, we understand the history of timber windows and doors. Because of this, we know how to create a stunning set of modern timber windows and doors that still look timeless and storied. Our designs use a wide range of wood types, including engineered Accoya timber, and we fit them with both old features like detailed handles and new ones like advanced double and triple glazing. For more information on getting them for your home or your business, contact us or start your trade quote!


Installers and other businesses can only work effectively if they have a reliable trade supply service – offering the highest performing products. Luckily, here at Dempsey Dyer we only supply the latest options from market leaders. This guarantees quality, performance and durability – regardless of the product choice.

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