Understanding U-Value Window

What is a U-value, and how does it apply to windows? U-values are ways of seeing how efficient a window is. Every window installed for homes in the UK must have a published U-value, which shows how well it deals with energy. With a low U-value, you can be sure that your window will keep your home warm and reduce your reliance your central heating.

A U-value is often used along with Window Energy Ratings, or WER’s, to describe how well a window performs. WER’s, though, are referring to the same thing – a U-value is the technical term. If your window has a U-value of below 1.6W/m2k, then it meets building regulations. However, the lower it gets, the better your windows will use energy for your home.

So, how do you make sure you get windows with low U-values? Most companies will be clear about the U-values of their window, so you can make a more informed investment if you know how the scores work. Also, you can refer to Window Energy Ratings, which are grades that windows can get. If the grade is higher, then the window will have better insulation and efficiency.

And, once you get windows with low U-values, you’ll feel the difference in your home straight away. Less cold air will pass into your home, and the same goes for draughts. As a result, your home will be more comfortable throughout the year, and it may have a longer lifespan as well. Due to this, investing in windows with low u-values is a brilliant way to enhance your home.

But how do you get windows with low U-values at low prices? With Double Glazing on the Web! You can find offers from installers near you in minutes, and you can compare them to save money!

What Does U-Value Mean In A Window?

U-values are an accurate way of seeing how well a window insulates your home. Older windows, with single-glazed glass, would have poor insulation, meaning that a lot of cold air could pass into your home. Not only that, warm air could escape in the same way, meaning that your whole home would become colder and less comfortable in the winter.

Modern windows, though, have double glazing, which does a lot to minimise heat loss. But, when you search for a window these days, nearly everybody talks about how double glazing alone can save you money on your energy bills. As a result, it’s a little more tricky to figure out which companies can back up their words or offer high-quality designs.

U-values and Window Energy Ratings exist for this very reason. Both systems can give you a quick indication of how well your window will perform inside your home. A U-value shows the amount of energy that can pass through your home in a given measurement – the lower the number, the lower the heat transfer, meaning the better the insulation.

Window Energy Ratings measure thermal efficiency in windows and give them a grade, rather than the accurate score U-values provide. Because of this, they’re arguably even easier to read. If you see a window with an A or A+ rating, the design achieves the highest thermal efficiency standards. And, with better U-values, you can be sure that these windows will save you more money on your energy bills over time!

buying double glazed windows

How to Measure the U-Value of A Window

One issue with U-values is they can be tricky to understand at first. U-values are measured by W/m2k, which means watts per square metre per Kelvin. In layman’s terms, this measurement defines the amount of energy that can pass through your window – the more watts allowed through, the more energy escapes. As a result, a lower u-value is more desirable than a higher one.

A useful figure to remember is 1.6W/m2k. If you see a window with a u-value above this, then it doesn’t comply with building regulations, meaning you won’t be able to install it for your home. However, if the window you’re looking at has lower u-values, it’ll improve your home’s performance. Old single-glazed windows have U-values around 2.5W/m2k on average, meaning any design will be an upgrade!

Another way to see just how well your windows will perform is to compare them to other elements of your home. For example, if you have cavity wall insulation, your home’s walls will likely have a U-value of around 0.7W/m2k. If you can get windows approaching this number, it shows that the designs will offer just as much insulation as the walls in your home.

Not only that, windows with lower U-values are better at other things, too. For example, better heat insulation usually comes part and parcel with reduced solar gain, thanks to double glazing that can reduce harmful UV rays entering your home. Not only that, your windows might last longer, and the colours of the profiles may be less likely to fade in the sunlight.

u-value window

Finding the U-Value of A Window

A U-value is essential for all windows in the UK. Without one, the window will not be legally compliant. Because of this, most double glazing installers are more than happy to publish their U-values and WER’s, especially if they’re good. However, if they aren’t obvious, you should be able to request them when you meet with installers.

From there, the main question becomes how you can find windows with low U-values at the right price. Unfortunately, some big brands will charge high prices for their windows, especially if they have low U-values. You could end up paying high travel costs and large premiums to cover their overheads, meaning you pay over the odds for a high-quality window.

However, local installers often provide the same window designs as those big companies without the high prices. Companies like these are usually smaller, meaning fewer overheads to cover, and they’ll be much closer to your home. Because of this, their installers can reach your home more quickly and personalise their installation service around your schedule.

Not only that, you can save even more when you find those installers through Double Glazing on the Web. You can get multiple quotes in minutes with us, and you can compare offers to get an even better deal. People who search for brand-new windows with us save up to 40% on their investment, and they find windows with low U-values every time.

Lower U-Value Window Prices with Double Glazing on the Web

You’ll get two things with Double Glazing on the Web, guaranteed. Firstly, you’ll find the lowest U-value designs to help you pick the right window for your home. We only put you in touch with the best local installers in your area, and they only work with high-quality manufacturers to offer their leading designs.

Secondly, you’ll get that window from an installer you can rely on. We extensively review our network to ensure that you don’t end up working with a rogue trader. Not only that, many of the companies we work with are Checkatrade and Which? members, meaning the installation of your window will be just as good as the design itself.

If you’d like to find a window with low U-values at low prices, fill in our online contact form to start the process. Alternatively, call us on 0800 015 5679 to ask us anything about windows and U-values!

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