Whether you’re replacing inefficient windows to cut your energy bills or are adding the finishing touches to an almost complete extension, buying windows can prove to be a daunting process for any homeowner. After all, there are a myriad of questions you need to answer such as:  

1. Which frame material offers the best lifespan?
2. What style of window will suit your property?
3. Which glazing type will be the most efficient?
4. What glass type will meet your individual needs?

Thankfully, buying windows needn’t be a headache full of unnecessary cost and sleepless nights. That is at least if you understand your options of frame material, frame style, glazing type, and glass type.

Within this windows buyer’s guide, we’ll reveal what you’ll need to have in mind when shopping for windows. We’ll do this with as little jargon as possible, making it easy to find the right window for your property.

Window Frame Materials

uPVC, timber, or aluminium – which is the best option for you? That’s the question many homeowners find themselves spending hour upon hour contemplating. But thankfully each of these materials ‘tick’ different boxes and suit distinct styles of property. 

Whilst windows have been made from timber historically, uPVC became a popular alternative from the 80’s onwards. Further advancements in manufacturing in the years that followed then saw virtually frameless aluminium windows grow in popularity. 

Today uPVC, timber and aluminium windows are readily available to homeowners on varying budgets. Whilst uPVC windows could cost as little as £600 per window, aluminium windows could set you back several hundred pounds more per window. 

uPVC

uPVC windows are often viewed as inferior to timber or aluminium alternatives. But in truth they offer a good middle ground when it comes to cost, maintenance, and longevity. Plus, they’re one of the most efficient options with them achieving a Window Energy Rating of up to A+. 

That’s not to say that there are no downsides to uPVC windows. Although they’re now available with coatings that imitate the grains of timber, they undoubtedly offer less character. uPVC windows can also be prone to chips, cracks, and breakages over time. 

Timber

The knots and grains found in wooden windows typically makes them the most charming option. But timber framed windows also offer the lowest level of thermal conductivity, helping to minimise heat loss through the frame. This is due to timbers natural ability to absorb and retain heat. 

But as with any natural material, wooden windows require a little more TLC. This could mean sealing and staining the timber every so often to ensure it’s protected from the elements and maintains it’s colouring. You’ll need to do this every 3-5 years or whenever you notice any weathering.

Aluminium

Aluminium windows are widely used on commercial properties or homes with an industrial style. As well as being far tougher than either uPVC or timber, metal framed windows allow for a thinner frame a greater glass area. This increases the amount of light allowed into a space. 

Unfortunately, metal allows heat to pass through easily and can therefore be less efficient than alternatives. To combat this many aluminium windows will have a thermal barrier within the frame. This won’t necessarily allow it to match the efficiency levels of timber, but avoids it being a nail in the coffin for aluminium. 

Window Frame Styles

So, you’ve chosen your frame material but now need to decide on your frame style. In most cases, this has little influence on efficiency or longevity and more impact on appearance and maintenance. It can, of course, also sway the cost of your windows with some styles being pricier than others. 

When choosing your frame style, you’ll need to consider whether they match the appearance of any existing windows. Plus, they could even have ramifications on planning permission if they are not of ‘similar appearance to those used in the construction of the house’. 

Whilst casement, sash, or tilt and turn windows typically result in minimal fuss from planning authorities, a bay window will often be treated as an extension. Because of this, you’ll possibly require planning permission however small the projection is. 

Casement 

It’s more than likely you’ve got casement windows on your home. They are available in a mix of combinations with the options for windows to be hinged on the side or at the top. Plus, your combination could include a mix of larger and smaller windows alongside each other. 

Sash

Designed to imitate styles popular during the Georgian, Victorian, and Edwardian periods, sash windows add a traditional touch to properties of any age. Unlike casement windows, sash windows feature two sashes that slide beneath each other vertically.  

Tilt and Turn

Featuring a dual hinge that allows the sash to open inwards, tilt and turn windows are more convenient to clean than other styles. Whilst they can be used almost anywhere, they are particularly suited for multi-storey properties such as flats. 

Bay

If you’re struggling with a dimly lit room, then a bay window could solve all your problems. Projecting outwards from the wall of your property, a bay window can feature multiple casement or sash windows in a semicircle or rectangular form. This will provide far more light than a single flush window would. 

Our Bestselling Windows

Window Glazing Types

With your choice of frame material and style settled, now comes the all-important pick of glazing types. Although it won’t impact your properties kerb appeal, it will impact the efficiency of your new windows. As well as help you slash your energy bills, this will make your property more or less attractive to potential buyers too. 

At the time of writing, homes built after 2002 are required to have double glazing of a specified rating. There are some exceptions to this, such as if a property had single-glazed windows prior or if planning restrictions are in place. But most homeowners will want either double or triple glazed to create a more comfortable home all-year round. 

Single

If truth be told, most people should avoid single glazed windows due to their poor efficiency. That said, you may be required to use them if planning or conservation regulations are enforced. If this is the case, you may be able to introduce secondary glazing to minimise heat loss and keep your energy bills under control. 

Double

Featuring two panes of glass that are connected by a spacer bar, double glazed windows allow you to create a far more comfortable living space throughout the year. This is as warm air is trapped between the panes to slow the speed at which heat escapes. 

Under the regulations at the time of writing, new buildings must feature C rated double glazed windows as a minimum. But you’re better suited fitting higher rated windows, such as those that have achieved an A or A+ rating. 

Triple

As you may have assumed, triple glazed windows simply feature an additional pane of glass. But it isn’t solely the use of a third pane that makes them more efficient, as the type of glass and coating used play an important role. 

In most cases triple glazed windows could be ‘overkill’, but they may be hugely beneficial in some scenarios. For example, triple glazed windows are a great choice in cooler rooms with a north-facing window or if you’re keen to make your property attractive to increasingly savvy buyers. 

When buying triple glazed windows, you may benefit from choosing those with noise-reducing outer panes. This is as the inner pane is more prone to vibrations caused by wind or other movement. But remember that any significant vibration could indicate the panes are faulty. 

Window Glass Types

Whether you’re fitting single, double or triple glazed windows, the glass used has a noticeable impact on their effectiveness too. This is particularly the case if you could benefit from specialty glazing, such as security or noise reducing glass. 

Low-E Glass

With up to 90% of the energy lost through windows being lost through its glass, it is evident that even double or triple glazing needs a helping hand. That’s what Low-E glass aims to do by introducing a microscopic coating that reflects heat better than glass alone.

Whilst this Low-E coating is largely unnoticeable it can impede natural daylight a little. That said, how much it restricts daylight is largely dependent upon the quality of the coating itself. 

Security Glass

As the name suggests, security glass is designed to withstand higher impact and therefore prevent breakages. It does this through the use of either laminated or toughened glass, with the latter being up to five times stronger than ordinary glass. 

When choosing security glass, consider laminated best for security and toughened glass ideal for safety. This is as whilst laminated glass holds the shards together with a PVB layer, toughened glass breaks into granular pieces with dulled edges. 

Noise Reducing Glass

Noise reducing glass could be a life saver if you live alongside a busy road, school, or anywhere else where noise is an issue. It reduces the amount of sound able to enter your home by using thicker glass panes as well as an additional inner pane in most cases. 

Many noise reducing windows go beyond simply introducing thicker or more panes. Some may use varying thicknesses of glass to disrupt soundwaves whilst others may use gasses between the panes to do the same. 

Leaded Glass

Although not as popular as it was in past centuries, leaded glass remains a great choice for period properties. Available in casement and sash windows, these windows feature both vertical and horizontal iron bars throughout each pane. 

Leaded glass is available with a choice of patterns, such as the classic Georgian or ever popular Diamond style. What’s more, leaded glass is ideal for stained glass if you want to introduce an extra layer of character on your property. 

Window Energy Efficiency 

Did you know that roughly 18% of heat within the home is lost through the windows? Meaning that whilst cheaper and less efficient windows will save you a buck in the short term, they’ll likely cost you far more over the years.  

Thankfully, there are only a few ratings you’ll need to keep an eye out for when buying windows. The BFRC’s Window Energy Rating makes it easy to compare windows whilst a U value and L value provide more granular insight. 

WER Rating 

When buying any window, the Window Energy Rating (WER) is a convenient and consistent way to judge their efficiency. Created by the British Fenestration Rating Council (BFRC), it’s made up of an alphabetical system in which each letter correlates to a specified level of kWh/m2 per year. 

The table below outlines each WER rating with anything between A and A++ considered to be energy positive. To determine a windows rating the solar gain, thermal losses, and air losses are taken into account.  

Thermal Efficiency (U Value) 

The maths behind a U value can get a little confusing but it’s simply a measurement of how much heat is loss per square meter through a given material. U values are used on a variety of building materials, such as brick, insulation and of course windows. 

When looking at U values you’re looking for the lowest number possible. The difference between windows can be significant, with a single window having a U value as high as 5.6W/m2K and a double glazed window having a U value as low as 1.4W/m2K.   

Solar Gain (G Value) 

Although Solar Gain is considered when giving a window its WER rating, window may advertise their Solar Gain separately. This value, which is often abbreviated to ‘G Value’, is a measurement of the amount of heat a window allows in by capturing UV rays. 

You may wonder why you’d care about the Solar Gain of a window. But with the UK having cool weather for most of the year, it’s beneficial if your windows can transfer some of the sun’s rays into heat during these cooler periods. That said, you’ll want a window with a lower Solar Gain if a rooms prone to overheating. 

Air Leakage (L Value)

Much like Solar Gain, this is factored when determining a windows WER rating. This value, which is commonly abbreviated to ‘L value’, measures the air able to leak by a windows construction. But it’s important not to confuse air leakage with ventilation, as the latter is controlled and will not compromise energy efficiency.  

Good quality windows should have an L value of 0.00W/m2K. This is as most windows on the market are fully airtight. Any air leakage that occurs is either a sign of a poorly constructed window or damaged window. 

Ready to Buy Your Windows? 

With your newfound knowledge of windows, you can now buy your windows with confidence. But if you’re still unsure, why not contact our award-winning team who will be happy to answer your remaining questions or walk you through our choice of windows.