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Leading UPVC and timber manufacturers

Operating since 1977

Range of Deceuninck, Alunet and Accoya systems

Manufactured in the UK

An introduction to Dempsey Dyer

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Timber Windows – Repairing vs Replacing

Windows are one of the most important aspects of any property when it comes to both style and performance. Whether you’re looking for profiles that are on-trend improve your kerb appeal or offer exceptional thermal performance and security benefits – or, most likely, both of these without compromise – then you know the right windows can’t be neglected.

Here at Dempsey Dyer, we manufacture market-leading timber windows for installers all across the UK. If your next project needs wooden window profiles with exceptional performance and aesthetics, you can rely on us.

As part of our informational pieces here on our website, we’ve got our team together and collated some of our insights from many years to help you understand when customers should opt to repair their timber windows vs when they should replace them.

If you’re looking for a new timber manufacturer to support you in your next and upcoming projects, you’ve come to the right place. Here at Dempsey Dyer, we’re one of the leading manufacturers of windows and doors, both timber and uPVC, and we’re able to help you and your business generate enquiries and win more business with our innovative designer tools. Talk to our team today!

When You Should Repair Timber Windows

In some cases, it may be the right decision to repair existing timber windows rather than replace their profiles entirely. First, you’ll want to be able to identify the signs that windows need repairing or replacing. Some tell-tale signs we’ve seen over the years range from physical deterioration to sub-par thermal performance – if heat is escaping out of your windows, now more than ever it’s vital to ask quickly to avoid wasting energy.

If aesthetics are a primary concern, then the good news is that the paintwork of your timber windows could be rejuvenated relatively easily. A fresh coat of paint can last almost 10 years on your wooden windows, so if that’s all it takes, it could be a decent option to buy you a little time until you want to replace your timber windows altogether.

From a performance point of view, you may have noticed rotting or warping having an effect on older timber window profiles. The good news is that if this is spotted early enough, it can be treated quickly and relatively easily. Skilled repairers might be able to separate any damaged sills from the rest of the profile and replace these separately, so you won’t have to swap out the whole window.

In all cases, whether you’re looking to repair or replace or just get some advice, it’s always best to consult the experts. If you’re handing delicate timber window components or potentially hazardous fumes on older window profiles, you’ll want to make sure your repairs are carried out safely and responsibly. At Dempsey Dyer, we offer plenty of advice and support, so speak to us today.

When You Should Replace Timber Windows

If repairing isn’t an option, you’ll want to look at replacing your existing timber windows with the latest, most stylish and highest performance profiles on the market – such as those manufactured by Dempsey Dyer. Our specialisation in the industry means that we know what it takes to make windows that are truly the best of the best.

Perhaps you’ve looked at repairing timber windows as the first option. If you’ve found rot and mould early enough, then it can be treated. But in some cases, this has developed too far and compromised the bulk of the window profile. As such, you won’t want to waste time and money trying to fix a broken timber window that will never perform as well as it needs to.

After all, you might end up having to do it all again sooner rather than that. In this case, replacing your timber windows will be the best time-efficient and cost-effective choice in the long run.

For many homeowners, the opportunity to replace their windows opens up a wealth of existing design opportunities. With trends always changing and evolving, you’ll want to keep up with the latest style options. Whether that’s in colours or hardware, since you last replaced your timber windows (if ever) there are sure to be plenty of new options on the market to suit any home and express a customer’s personality uniquely.

From a thermal efficiency point of view, there’s never been a more pertinent time to replace older, outdated timber windows. This is because many wooden windows feature single glazing. Compared to double or triple glazing, single glazed windows suffer from sub-par energy performance, with hot air easily escaping. With upgrades to new double glazed timber windows, homeowners can save money on heating bills and stay more comfortable all year, all ways.

Market-Leading Timber Windows from Dempsey Dyer

Choose Dempsey Dyer for the highest quality replacement timber windows on the market. With many years of experience behind us and many more ahead, you can rely on us at your one-stop shop for timber windows and doors that you can count on. Get in touch with us today.

Your One-Stop Shop

Here at Dempsey Dyer, we’ve been manufacturing top-quality timber and uPVC windows and doors for the trade for many years. In that time, we’ve built an excellent reputation and relationship with our customers, allowing us to understand what it takes to be the very best and provide installers with exactly what they need.

We’re proud to be many customers’ ‘one-stop shop’ for expertly manufactured windows and doors. With service and products that you can count on, there’s always a reason (or three) to choose Dempsey Dyer. As part of this offering, we often talk to our customers about our ‘good, better, best’ options – for any project, we have the products that will work for you.

In this guide, we’ll take you through our ‘good, better, best’ offering and demonstrate what this means for you – and why you should partner with us for your upcoming projects. With online lead generation tools and innovative window designer software, plus our exceptional product range of windows and doors, there are so many reasons to choose Dempsey Dyer – your one-stop shop for timber and uPVC home improvements!

One-Stop Shop for Windows

If you’re looking for market-leading uPVC and timber windows for your next installations, you’ve come to the right here. We manufacture high quality profiles from Deceuninck in a wide range of styles including casement flush sash, mock sash and Stormproof.

Classic casement windows are enduringly popular, boasting a simplicity that suits all kinds of homes and customisation capability to suit any property and express homeowners’ personalities. Plus, with the current and ongoing focus on thermal efficiency, modern casement windows with double glazing are an excellent choice and an effective upgrade on older, outdated profiles.

For a higher-end option, we’ve developed our own Stormproof Windows. These bridge the gap between timber and uPVC, providing a timber-look style coupled with exceptional performance. Stormproof wood-effect windows are a more comprehensive investment that can be further enhanced with a range of hardware options and other accessories to complete the look and further bolster the all-around reliability.

Whether your customers are looking for simplicity done perfectly or a unique design at the top of the market, you can rely on Dempsey Dyer as your one-stop shop for windows to have what you need.

One-Stop Shop for Doors

Our range of doors is as comprehensive as our windows, further cementing us as the one-stop shop for door manufacturing in the UK. As customers become more attuned to the wider market and surer of what they’re looking for, our product range has quite rightly expanded to adapt to ensure we offer exactly what people need.

Timber and uPVC doors continue to be popular choices for both modern and traditional homes alike. We offer most configurations in both materials, so whether you’re looking for sliding patio doors, French doors, bifold doors or classic entrance doors, we can help. Work with your customers and us to design a door that’s right for them, in the best material, enhanced with the right hardware, and manufactured to these specifications perfectly.

Composite doors, similarly, have become increasingly popular, combining the performance of uPVC with the look and feel of timber, for the best of both worlds. We offer market-leading composite doors as part of our one-stop shop for doors. So as with our windows, whether you’re looking for something classic or cutting-edge, we can help.

Choose Dempsey Dyer for the doors that you need for your next projects, manufactured to your specifications, to exceed your expectations, every time.

Dempsey Dyer – Your One-Stop Shop

For the best windows and doors on the market, expertly manufactured to suit you, choose Dempsey Dyer. We pride ourselves on having something available for all kinds of projects with our ‘good, better, best’ offering, so we’ll always have what you need. Get in touch with us today to join us and find out more.

How Aluminium Windows Have Become More Thermally Efficient

With energy efficiency at the forefront of everyone’s minds no matter where they are in the journey – from manufacturers and tradespeople to homeowners – it’s only right that there is a lot of discussion around which type of windows and doors are the most thermally efficient.

One of the most popular types of windows at the moment is aluminium. This material offers a distinctive, striking aesthetic that is ideal for modern homes looking to retain their up to date appeal or even traditional homes looking to bring themselves up to date.

But how does aluminium compare to timber and uPVC as an energy efficient window? It’s one of the products we offer here at Dempsey Dyer, and thermal efficiency is highly important to us, so we want to make sure our installers and homeowners stay educated about its properties to make an informed decision. That’s why we’ve put together this guide on aluminium windows’ thermal efficiency. Read on to find out more.

Older Aluminium Windows

Several years ago, aluminium windows were not thought to be one of the most energy efficient options on the window market. That’s because, as a material, aluminium has high levels of heat transference. So, once installed, when customers would heat the inside of their homes, the windows would absorb this heat – and its transference properties would pass the warmth to the outside world, so it was lost.

From an energy efficiency perspective, this is far from ideal. If homeowners are spending money and energy heating their homes, the last thing they want is for it to escape – what’s more, frustratingly, with the help of their windows, rather than them stopping it. This leads to lost heat and therefore lost money.

Additionally, aluminium windows’ thermal transference properties led to them expanding in heat. With the profiles changing along with the temperature, the window seals would become damaged, leading to condensation, which is as unsightly as it is unhealthy. Older aluminium windows could even break away from the glass as a result of this expansion, which only exacerbated the issue of them losing heat too!

However, this changed with the development and popularity of a thermal break for aluminium windows.

Thermal Breaks – Explained

A thermal break is what has made aluminium windows more viable and more popular as a result. So what is a thermal break? For those who are not aware of what it is or perhaps more likely how it works – put simply, a thermal break separates the inside of the outside from the window.

This means that when one side of the window becomes too hot, there is an extra layer in between that stops the same thing from happening on the other. It’s the same case for the cold, too.

A thermal break is an excellent addition to aluminium windows. With this in place, it reduces the issues that these profiles were facing previously – condensation and heat transference, and therefore extra expensive for customers in all cases. Now, with a thermal break, aluminium windows are as modern in their performance as they are in their aesthetics.

Modern Aluminium Windows from Dempsey Dyer

Here at Dempsey Dyer, we are at the forefront of development in the fenestration manufacturing sector. Our timber, uPVC and aluminium windows and doors perform expertly, with a range of options available, making them ideal for modern homes or even traditional properties looking for a modernisation.

Aluminium windows are thermally broken to ensure they limit condensation and lost heat. This means they will stay looking at performing at their best for longer, so homeowners can be sure that they have made the right investment financially and ecologically.

Sustainability and thermal efficiency are hot topics, which is why we’re keen to inform our customers about aluminium windows and how they relate to this. With energy efficient glass and profiles manufactured with thermal properties in mind, homeowners will be sure to save money on their bills and be proud of their investment.

Talk to our team today or request your free online quote to find out more.

Guide to Window Energy Efficiency Ratings

Window energy efficiency ratings have become increasingly important for homeowners, and therefore it is key for tradespeople and installers to understand as well. With energy efficiency ratings explained, you will be better able to get across the importance of these scores – and how windows perform in relation to them.

At Dempsey Dyer, energy efficiency is important for us as manufacturers. We know that everybody wants to save money on their energy bills, so they need profiles that are thermally efficient to keep the heat in and reduce the strain on central heating systems.

To help our installer customers and end-user homeowners understand window energy efficiency ratings, we’ve put together this complete guide with all the information you need. As an introduction to energy efficiency scores, this should give you a good starting point. If you have any questions about energy ratings or would like to talk about our expertly manufactured windows and doors, we welcome you to get in touch with our team today.

What is a Window Energy Rating?

A window energy rating (or WER) is the score relating to its thermal efficiency and heat transference. It’s a scale between E (at the lower end) and A+ at the top. This is generally the case, as different energy review bodies will have slightly different metrics, although some scoring systems may vary slightly.

You can find out more about the specific examples by visiting Certass, BSI and British Fenestration Rating Council respectively.

To place windows on the scale, a formula is used based on the total solar heat transmittance – that is, the amount of heat from the sun that can pass through the glass, also known as the g-value – plus the U-value of the whole window, frame and glass combined, which is how well the window keeps heat in your home without letting it escape.

While the formula itself may be complicated, you can see how these factors are massively important to homeowners and therefore installers and manufacturers, since they clearly assess how thermally efficient a window is – and as such, how much money customers can save on heating.

A formula is helpful since it makes the scoring system consistent with other products, so customers can easily see how energy efficient one type of window is compared to another, or how a window performs next to a door, for example, or even a washing machine or lightbulb!

How are Window Energy Ratings Given?

As you can tell from the formula above, the energy rating takes into account the glass and the frame combined. As such, energy efficiency ratings are not attributed to one instead of the other, like the frame or the glass individually – instead, it’s the whole unit.

That means that the manufacturing process is key here, which is why understanding energy efficiency ratings are so important to us as manufacturers. At the point when these window elements are combined, the energy rating can be given. If poor quality glass is installed into sub-par frames (or vice versa) the score will drop and the overall product will not score as well.

Window energy efficiency ratings keenly and intelligently are based on the whole product, so customers can be reassured that they are getting the full package that performs as well as it needs to once installed. This makes the WER system a trusted resource throughout the process.

Benefits of Energy Rated Windows

Here at Dempsey Dyer, we’re all about educating our customers on the benefits of our windows and how they will improve the end users’ lifestyle. As such, now you know how window are scored with the energy efficiency ratings systems, here are some of the key benefits of why homeowners should invest in them:

Trusted Scheme

Everybody can rely on numbers and formulae. With WER scored by a set system that’s easy to compare within the industry and across other sectors, it’s easy to rely on. Like results from other neutral, impartial accreditation bodies, window energy efficiency ratings will give you the facts.

Quality Manufacturing

With an impartial scoring system in place to go by, WER forces (quite rightly) manufacturers to create quality products on all fronts. They can’t compromise on any elements, such as the frame or the glass, since the score of calculated combined. As a result, energy rated windows are made to impress – both the efficiency score and customers.

Saving Money

Perhaps the most important benefit for homeowners (understandably) is how following the scores of the window energy efficiency rating system can save them money. With windows that score better on WER, customers will enjoy improved heat retention and reduced heat loss – meaning less reliance on energy bills and more disposable income!

Energy Efficient Windows from Dempsey Dyer

Here at Dempsey Dyer, we’re passionate about sustainability, and educating our customers on and abiding by the regulations of the window energy efficiency ratings system is a significant part of this. That’s why we wanted to put together this guide to explain not only why it’s so important to homeowners – but also why we work towards this.

Our windows and doors achieve excellent energy efficiency ratings, so end users can save money on energy bills in line with this trusted scheme.

For more information about how WER relate to our products, get in touch with our team. What’s more, you can use our online quoting tool to get a free quote for energy efficient windows and doors to start saving money – and the planet – today.

What’s the Best Kind of Patio Door?

During the summer, our gardens are in use far more than during the winter. By extension, we use our back doors a lot more, whether we have them swung wide open to let the air in or we just like to look out of them at the cool morning air and the sunrise that is bouncing off the colours of the lovely flowers we have in bloom. We’re in the height of summer now, so you’ve probably found yourself interacting with your patio door more often than you have for the rest of the year. When you’re doing so, it might be time to ask yourself, is this installation as good as it could be? Maybe you moved into your current home recently, and this is the first time you’ve really spent a lot of time noticing the condition of your patio door. Maybe you’ve had the same patio door for years and are noticing that it’s time for an upgrade. Whatever the reason, you’ve never had more choices available for the perfect back door! 

With plenty of options to choose from, it can be overwhelming to decide how to customise your patio doors.  Luckily, here at Dempsey Dyer, we supply a patio door that is bespoke to your customers’ needs. To find out more, read on. 

Sliding Doors

An all-time classic and probably the most common variety of patio doors, the sliding door exploded in popularity due to its ability to provide exceptional, uninterrupted views of the garden. Doubling up as large windows and doors, these installations provide a fantastic way of connecting the outdoors with the inside of your home. Our sliding doors come in three materials: timber, uPVC and aluminium. These doors offer fantastic views for end users, letting them enjoy the outside world more. 

Bifold Doors

If you’re looking for the absolute maximum opening potential, then the modern bifold door is an exceptional choice. Bifold doors fold into each other through individual panels and are opened either from the centre or the side. Through this folding mechanism, otherwise known as concertina, these doors provide:

  • Thermally efficient, so warm air can be retained. 
  • Removing a selection of the wall opens your home to the outside world.
  • Letting natural light in your customers’ homes saves money on your energy bills.

Your patio and interior will become one when these doors are fully open. When you don’t want to have them open, one panel will be designed to operate independently of the others, allowing you to use a regular door for your patio entranceway, saving you the hassle of unfolding doors when you want to enter and exit quickly and easily. 

A disadvantage of the bifold door is that it only works when combined with large wall space to get the concertina design’s full effect. Furthermore, the panels are individually separated and thus, do not provide the uninterrupted views that one can achieve with sliding doors. As a result, the bifold door is perfect for homeowners looking to open up their homes during the summer to the outside.

French Doors

If you’re an end user who doesn’t have space for a bifold door then the French door is an ideal option. The patio door and the French door offer a similar style. Many homeowners often confuse patio doors with French doors, and understandably so! The French door is the simplest option of the three, but that is in no way a bad thing. The French door gives the home a great and easy-to-use exit that provides good views into the back garden and can be placed in a small space along a wall, allowing for maximum heat retention in the winter. The French door can also be opened like a bifold door, allowing for huge airflow throughout the home. 

The French door requires the least amount of maintenance among the three options due to its small size in comparison. The French door is perfect for the homeowner looking for a simple option or for the homeowner that wants to maximise their wall space and isn’t particularly interested in all-encompassing views of their garden.

Patio Doors from Dempsey Dyer

We hope that this article has helped you understand the difference between sliding doors and patio doors. Both doors offer popular choices for the customer as they come in slim sightlines, allowing for  beautiful views of the outside. Our friendly and professional team have decades of experience installing doors, so we are on hand to help you. 

Whatever you choose you’ll get the absolute best in modern performance when you choose Dempsey Dyer for your home improvements! Get a free quote by using our online pricing tool!


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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