Window Styles: Costs, Materials and Design Details Explained

Choosing window styles for your home can be a daunting process, whether you are renovating a house, building an extension or starting a self build. The sheer breadth of choice and the various differences in window costs and their quality can seem overwhelming.

Windows are without doubt a big house purchase — and one that can really make or break your house design so it pays to get the window style right.

From costs, to materials and ideas to inspire, our buyer's guide to window styles will help you start your research.

Window Styles Through The Years

Looking back through history, windows on cottage elevations or Georgian style homes were smaller than the bigger glazed apertures synonymous with modern design. 

Although larger window styles bring the benefit of letting in more natural light, windows must be sympathetic to the house they adorn. 

If you are renovating a house it would be prudent to look at the original windows — it might well be a planning condition to replace like for like. 

If you're taking on a self build perhaps this is the chance to go big. Whatever window style you choose, it has got to meet energy efficiency standards, too. So there's lots to consider. 

How to Position Windows on Your Home

It is often said that if the elevation is the face of the house, then the windows are the eyes. So beyond all the practical and performance issues, the window style you choose must look good. And that is down to three main factors:

• the positioning of the windows
• the shape of the windows 
• and, finally, the window itself. 

So many people get the first two wrong that it’s almost irrelevant how nice the actual windows are.

This is equally as important whether you’re building a contemporary or traditional-style house — and a simple walk around any neighbourhood will show you how many designers get the window style wrong at the design stage. 

Obviously the layout of the house will influence the positioning of windows on elevations, but just as important is how these windows fit in with the elevation itself, from outside. The shape of the house will have a key influence here. A long, low, horizontal house might be improved further by a narrow horizontal window style to accentuate the length. Likewise, little old cottages can look quite odd with large glazed openings puncturing the thick walls.

There is a surprising amount of science behind the design of windows. The golden ratio, first developed in classical architecture when mathematics was just as critical to design as aesthetics, is still used today as a short cut to good proportions. It says that the ratio between proportions should be 1:1.618, meaning that a vertical sash window at 800mm wide should be 1,300mm tall. The ogee curve, which is a derivative of the golden ratio, is also used to assess this aesthetic standard.

(MORE: Window Seat Ideas)

How to Choose the Right Window Styles for Your House

Your choice of windows should be based on the style and, in the case of renovation projects, era, of your house. 

As glazing got progressively cheaper and easier to work with over the centuries, the size of our windows grew. As a result, those looking to recreate or renovate older period homes and cottages would do well to research the original styles and get a modern window company to replicate where possible. 

Small casement windows are associated with cottages, while homes built in the Georgian and early Victorian era are dominated by multi-pane, vertically orientated sliding sash windows. 

That all changed with the advent of modernism in the early 20th century. If your home is of that era, or the style in which you are looking to build is contemporary, then simplicity is the watchword: minimising not just the amount of framing (say, on casements) but also the frame width itself. So you could consider the more modern the house (or style) the bigger and cleaner the glazing should be.

(MORE: Explore the new Trend for Bifold windows)

Costs

How Much do Different Window Styles Cost?

Window prices vary depending on the size of your project and the material you choose.

PVCu windows and some softwood options are great for those on a budget and can cost between £5,000 - £20,000, depending on project size.

At the other end of the cost spectrum, for aluminium windows or composite windows you'd be looking at £8,000 - £25,000. 

It’s also useful to rank window costs on a square metre basis. 

Suppliers tend to dislike this because you don’t buy windows by the square metre: they are priced individually and generally the larger the actual window, the less it costs per square metre, so reducing a window range down to a square metre price is never going to produce an accurate pricing method. 

But from a comparison point of view, it’s a very useful tool.

Take the total amount quoted to supply windows and divide by the area of the window openings to derive the square metre rates.

Window Materials Explained

Having established the position, size and shape of the window, it’s time to choose the supplier, which starts with the frame itself. Each supplier has its own selling focuses, but the key early decision is on the material itself. Window frames tend to come in one of three main choices: PVCu (plastic), timber, or metal/alloy (aluminium or steel).

PVCu Windows

PVCu dominates the replacement windows market and for good reason: it’s usually the cheapest option, manufactured at scale, is largely dimensionally stable (it won’t shrink or warp), is pre-coloured (no painting) in a range of finishes (some impressively wood-like) and requires very little ongoing maintenance. It comes in a range of moulded styles (suiting both traditional and modern homes) and has come a long way in terms of mimicking timber (and aluminium) appearances.

The key negatives are that the frames tend to be a little chunkier than the alternatives and not everyone thinks it is appropriate for period (or indeed period-style) homes.

One of the design elements that very few PVCu window suppliers seem to get right is the ability for the opening casement to close so that it is flush with the frame, and also consistent in terms the thickness of the sightlines, where the frames in the window all line up with each other. Most homeowners don’t care about that type of thing — but of course, you should.

Pros:

• Cheapest overall although costs vary with quality
• Low-maintenance
• Range of moulded styles

Cons:

• Can look cheap
• Can reduce the value of period homes
• Not easy to repair
• Doors can be weak

Costs: £5,000-£15,000 for a one-off house

Timber Windows

Timber’s main selling point is its feel and authenticity for period-style homes.There is no better material for replicating a traditional style and detailing than timber. And that tactility and texture of timber has broad appeal beyond the traditionalists. Increasingly, builders of modern homes might look to solid chunky oak in order to frame their large pieces of glass.

The problem for most people is maintenance (on all timbers) and dimensional stability/durability.That said, nothing looks quite like a timber sash, and most timber window suppliers will pre-treat and paint the windows, but they will need attention every 5-10 years or so.

Softwood Windows

Softwood windows are well worth considering as they are suited to both contemporary and traditional style projects and are achievable even on a tight budget. But they do require more maintenance than other materials so may not be suitable for everyone.

Pros:

• Nothing can beat the tactility and detailing of a timber framed window
• Softwood is popular among those on a limited budget as they are the cheapest option if glazed and decorated on site
• Can be stained, but are usually painted
• Suits both contemporary and traditional style homes

Cons:

• On-site glazing carries a risk of double-glazing failure (i.e. misted units)
• Factory glazing lowers the risk but costs more
• Softwood requires repainting every few years

Expect to pay: £6,000-£15,000, less if ‘DIYed’ on site

Best softwoods to choose: Douglas fir is a very stable, durable softwood while European Redwood (also known as Scots Pine) is less prone to dimensional change and movement.

Hardwood Windows

Hardwood windows are great choices for traditional-style homes, but tend to me more expensive than softwood.

Pros:

• Have a tighter grain than softwoods, making them more stable and durable
• Can be treated to be further stabilised
• Most popular on traditional-style homes
• Usually stained

Cons: 

• It’s expensive — anything up to four times the cost of softwood

Costs: Between £8,000 and £20,000

(MORE: Timber windows)

Aluminium Windows

Aluminium is undoubtedly the framing material of the moment. It is super strong which results in the ability to achieve very slim frame widths while easily accommodating heavy triple glazing. It comes pre-finished in any RAL colour (not just anthracite!) and it perfectly suits the modern desire for small frames, minimal bars, and maximum glass. It’s almost completely maintenance free and is totally dimensionally stable.

And aluminium windows aren't just for contemporary homes. What has changed over the past year or so is that it is increasingly being specified on more period-style homes. “Aluminium is being used in more and more period properties as customers realise the potential to create period looks,” says Neil Ginger, CEO of Origin. “We offer Georgian bars, midrails on doors and woodgrain finishes on our aluminium products, enabling us to meet the stylistic requirements of a period property with none of the maintenance and upkeep of wood.”

Pros:

• Energy efficient
• Last up to 40 years
• Little maintenance

Cons:

• It can be up to 20% more expensive than PUVu windows
• In some cases the colour can be limited

Costs: £8,000 - £18,000

Composite Windows

If you’re struggling with the choice of materials, there is a compromise — the so-called composite systems that mix different framing materials inside and out.

Pros:

• Best of both worlds as they usually consist of timber windows with a weather-proof capping, such as aluminium strips or plastic
• Can withstand harsh climates (widely used in such as Canada and Sweden)
• Great for triple-glazing
• Complement modern designs
• Low maintenance but offer the warmth of timber

Cons:

• Expensive
• Unlikely to be made to standard UK sizes if ordered from the Continent

Costs: Between £10,000 and £25,000 — expect to pay 25% more for triple glazing

Steel Windows

Steel windows are fast becoming a popular choice with people that want to create a European style finish or want to add a modern touch to a period renovation.

Pros:

• Popular among contemporary-style homes but increasingly popular in period properties (particularly for Belgian doors)
• Low maintenance
• Produce classic, elegant-looking frames

Cons:

• To increase the thermal qualities, include glass units with argon in the cavities
• Can be expensive

Costs: Between £7,000 and £21,000

What are the Main Types of Window Styles

Casement Windows

Casement windows are windows that are attached to their frame by side hinges.

In contemporary house styles, side hung and awning formations work well as there is no mullion to interrupt the view. Here are the casement types:

• Side Hung: The most recognisable casement. It is hinged at the side for easy opening
• Top Light: A fixed pane divided from a narrow glazed top-hinged casement
• Top Hung/Awning: A casement window that is hinged at the top. Perfect for wet climates as it blocks out rain
• Bottom Hung/Hopper: A casement window that is hinged at the bottom. Most commonly used in a basement
• Centre Hinge/Pivot: A window that is hinged in the centre to allow for a wider opening, it requires less of a swinging clearance

Pros and cons of casement windows include:

• Large casements tend to be the cheapest
• Costs tend to be lower because they are made in modular, standard sizes
• Great for ventilating rooms but as they can open wide, this might cause concern for those with small children or animals

Tilt and Turn Windows

Tilt and turn windows can either be opened to tilt inwards, usually from the top down, for ventilation, or to open from side hinges inwards (a bit like a casement in reverse). Tilt and turn windows look best on modern designs. 

Pros and cons of tilt and turn windows:

• They are typically made to order, increasing the cost
• Secure
• Great for smaller rooms where saving space is a priority

Fixed Windows

Fixed windows are just that, fixed, so they don’t open out or let in any ventilation. However, they do maximise opportunities for natural light throughout a home. As they don’t need to be made to incorporate a opening mechanism, there are endless designs and styles to play around with.

• Provides light in wasted spaces
• Can create interesting designs
• Usually the cheapest style of window

Sash Windows

Sash windows are windows with one or two sashes, split into a number of panes, that slide vertically or, in some cases, horizontally. This window style is still widely used on traditional-style new builds. Sizes are typically non standard but windows need to be in proport­ion to the house, so are often bespoke.

• Timber sash windows require maintenance
• Typically have vertical tracks so won’t fill up with leaves and detritus

Roof Windows

Introducing roof windows can work wonders to bring in natural light where conventional windows can’t be installed.

Roof lanterns are architectural features that are fitted into the roof to allow light into the space below. They take many shapes and configurations and can be made from aluminium, timber or PVCu. 

Rooflights are windows fitted into the roof. They can lie flush with the roofline or sit slightly proud of it. They come in various materials. Some are opened manually whilst others can be operated by panels on the wall or remote control. Fixed windows that follow the roofline are typically known as skylights.

• Rooflights are great for ‘rooms in the roof’ in loft conversions or one-and-a-half storey homes, which are steadily becoming more popular options among self-builders with height restrictions
• Skylights are increasingly seen in terraced houses with side return extensions, providing light deeper into the floorplan
• Roof lanterns offer a greater opportunity to introduce the maximum amount of light and help to achieve the illusion of extra head-height in extensions with flat roofs

Bay Windows

A bay window projects outward from the face of a building, forming a recess within a room. A bay window can span more than one storey, as seen in many Victorian and Edwardian homes, and can be used in self build designs to create window seats and breakfast nooks. 

There are different types of styles of bay windows including:

• Canted: This means the window is formed of straight front and angled sides
• Bow: Where the window structure is architecturally curved
• Oriel: Starting above ground level, an oriel window is supported by corbels or brackets as it jetties out from the main walls of a building

High-level Windows 

These are sometimes used to retain privacy but increase natural light or ventilation. In modern energy efficient houses, clerestory windows have been used in solar gain strategy and paired with stone, brick or concrete. In hotter parts of the day the elevated window position gains heat and essentially uses the structure below as a heat bank.

• Let in extra light and ventilation
• Great for rooms with high ceilings

Glazed Gables

An architecturally impressive way to flood a home with light, glazed gables don’t have to break the budget on a self build or extension if planned into the design early on. 

• Add ‘wow factor’ to any room
• Can suit traditional cottages just as well as modern designs

Glazing

Window Glazing Options

Triple glazing is rapidly becoming a standard solution for today’s window suppliers – particularly in the aluminium space – and is certainly worth considering. The increase in energy performance is significant and well known. What is less well known is the improvement in acoustic performance. Double-glazed windows can achieve an acoustic performance in the range of Rw32. This can be adjusted into the low 40s with a thicker gap between the panes or with some types of triple glazing, such as Bereco’s Ambient acoustic windows — the difference on a busy road between a good night’s sleep and a disrupted one. 

So how much will the triple glazing premium cost? Some of the European-based manufacturers such as Internorm and Velfac are so busy creating triple-glazed windows for their European customers that it’s a bit of a pain to create double glazing for us Brits. As a result, the extra price of the glass can often be measured in the low single percentage points — if at all.

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Low-emissivity or ‘low-E’ glass (as it is more commonly known) is a type of glazing designed specifically to prevent heat escaping through windows. Low-E double glazing meets Building Regulations in the UK (such as Part L1B in England) for replacement windows and new windows for extensions.

Benefits include:

• Can reduce heat loss by at least as four or five times compared with single glazing
• Solar control glass can be specified to educe excessive solar gain in the summer for areas of the home susceptible to overheating

How Big can Windows be Without Framing?

Most window suppliers are limited by the weight of the glazing unit rather than the size — the pressure on hinge systems being the key issue. Most suppliers struggle to go beyond around 2-2.5m2 for opening units, but fixed systems (that don’t open) can be up to around 7m2. 

Beyond that size, you’re looking at structural glazing — where the glass plays a structural, loadbearing role itself. The glass is thicker and stronger than that used in standard window solutions and it’s fixed with structural grade silicone. With structural glass the only limitation on glazing sizes is access to the site and, of course, budget.

Questions to Ask Your Window Supplier

What Questions Should you be Asking? 

It pays to ask lots of questions when looking at window styles to really gauge the window supplier and their products. Here are some key questions to ask:

• Where is the material from? If it’s timber, is it responsibly sourced? If it’s aluminium, is it consistently sourced or made from various elements? Will it give a smooth finish?
• If you’re looking for a modern, sleek appearance, you’ll need to talk sightlines. How thin is the sightline? Some suppliers such as Origin can produce frames as thin as 65mm and even lower for fixed units, meaning less frame, more glass and more view. Do the external frames overlap? Some suppliers can offer a flush finish which is good for a simpler, smarter external appearance.
• Customer service. What are the warranties and service offered by the supplier?
• Check on the frame basics. Does the frame have a thermal break in it? This is critical in terms of energy performance (the frame doesn’t directly transition between inside and out without an air gap).
  
  

Lead Times

How to Order Windows

This very much depends on whether you’re opting for off-the-shelf windows or bespoke products, and can also differ from company to company.

A general lead time would be around 12 weeks, however, it goes without saying that bespoke windows will inevitably carry longer lead times and with material shortages at the moment, you'll need to take this into account, too. 

It is best to not order too early on in the project in case amendments to the building design or aperture sizes occur.

Mixing Window Styles

When mixing window styles, there are a few approaches to consider.

By choosing windows in keeping with the style and age of your building, you'll create an authentic look. It's worth taking advice or researching styles to ensure you make a choice based on the heritage of a building rather than your aesthetic choices. In fact, if you are replacing windows or attempting to add new windows in a listed building for example, this will be crucial. 

However, rather than creating a pastiche of the original building, when adding new windows into extensions, for example, creating a contrast between old and modern can be effective and in keeping.