Windows FAQs

What is double glazing?

A double glazed window consists of two panes of glass which are separated by a small cavity. This cavity is then filled with an inert gas, usually Argon but sometimes Krypton, as they are poor conductors of heat. This reduces the amount of heat that is able to escape through the window, therefore, making your home more energy efficient.

What is triple glazing?

Triple glazing works in the same way as double except there is an additional pane of glass and an additional cavity filled with Argon or Krypton. As well as improving energy efficiency further, triple glazing also provides better acoustic insulation and security than double glazing.

What is the cost of double glazing?

As windows are fitted on a project-by-project basis, there is no standard cost for double glazing. The cost will, however, change in accordance with a number of factors, including:

• the number of windows that are required
• the size of each window
• the time it will take to install them
• any extras e.g. window furniture, decorative glass and the window material

Before we carry out any work, one of our experienced surveyors will pay you a visit to learn exactly what you’re looking for in new windows. Next, they will take the necessary measurements before providing you with a free, no-obligation quote so there is no pressure to buy anything from us.

Our customers also have access to our excellent selection of finance options, which they can use to spread out the cost of paying for new windows.

What are Window Energy Ratings (WER)?

When looking for new windows, you may have noticed an installer mentioning the Window Energy Rating (WER) of a particular window. This system is used to denote the overall thermal performance of a window.

The lowest rating is G and ratings go up as high as A++. Any new or replacement windows must have at least a rating of C in order to comply with current UK Building Regulations. Here at Droylsden Glass, all our windows are able to achieve ratings of A and some can achieve A+.

What are U-values?

U-values are another common way for installers to demonstrate the energy efficiency of a window, however, you might see them mentioned when looking for new doors and conservatories too. U-values denote how much heat can escape through the glass, also known as thermal transmittance, and they are measured in Kilowatt-hours, per square metre, per year (W/m²k).

So if we take our aluminium windows as an example:

They have a U-value of 1.0 W/m²k. This means that 1 kilowatt of energy is lost through every square metre of the window every year.

Will I need to get planning permission for new windows?

Replacement windows do not usually require planning permission, especially if the replacements are similar in appearance to the original windows. However, just to be sure, it’s always worth contacting your local planning authority before starting any home improvement project. There are various scenarios where planning permission is likely to be required too, including:

• When your property is a listed building
• If you live in a conservation area
• Replacing the windows on a flat or maisonette
• If your property is subject to an Article 4 direction

If you have any questions regarding planning permission for windows, feel free to contact one of our experts for further advice.

Which windows are best suited to the style of my home?

Modern windows are highly adaptable so can be customised to suit a variety of properties. Our uPVC windows, for example, can be finished in a variety of woodgrain textures. This gives them a similar appearance to timber, which is perfect for any period properties. For more modern homes, you can’t go wrong with aluminium windows. Their crisp, slender frames absolutely epitomise contemporary style.

Any products that we install come tailor-made to the property, ensuring they are a perfect fit every time. From the style of the framing to the finish and window furniture, there’s ample opportunity to alter their look to suit your property’s unique style, including with our sliding sash windows and Residence 9 windows.

What’s the difference between flush casement windows and casement windows?

The main difference between these two styles of window is their appearance. Flush casement windows feature a sash that sits flush with the window frame, whereas the sash on a casement window protrudes out slightly. Flush sash windows also utilise graf welding technology, creating seamless joints like those on traditional timber windows.

In terms of thermal efficiency, both are excellent choices and there is very little between the two. Here at Droylsden Glass, our flush casements and standard casements are able to achieve Window Energy Ratings (WER) of A+ and A respectively.