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Why get double glazing?

  • Save up to £195 per year on energy bills
  • Improve your property's value
  • Reduce outside noise

Roof Windows and Velux Windows Costs

Roof windows make a room feel bright and spacious with natural light

Roof window prices tend to start at around £570

Complete the form above to receive free quotes for your new windows

Roof windows allow an extra influx of daylight into your room. And while getting your windows with double glazing costs more, it's worth it for the extra insulation.

That way you can make your room feel more spacious, without compromising on warmth.

We're here to run through all the different kinds of roof windows – from small skylights which don’t even open to huge glass roofs through which you can gaze up at the heavens.

However, if you'd like to see the best and brightest windows out there, you can fill in this form to get bespoke quotes. All you have to do is simply answer a few questions on the form. We'll then pass on your details to our trusted suppliers, who'll be in touch with quotes for you to compare.

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Types of roof windows

Velux rooflights

Skylights are windows that are set into the roof at the same angle as the roof, whether it’s flat or sloping.

Fixed or non-opening roof lights allow daylight into your room but don’t open. This can be a simpler and less expensive option than an opening window, especially if it is out of reach and would have to be operated remotely.

Opening roof lights allow you to ventilate a room – which is particularly useful in a kitchen or bathroom where heat and moisture can build up. They can also serve as a means of escape, or provide access to a roof terrace. You can choose windows that open partially or fully, and which are hinged or sliding.

Domed or curved rooflights have a dome over the top of the flat glass pane – which can look striking and is useful if you have a flat roof, as rainwater will slide off easily. This helps keep the glass clean and your view clear. (It’s worth mentioning here that flat skylights should actually always be installed at a slight angle so rainwater can run off.)

Lantern or pyramid roof lights are made of several panes of glass in, as the name suggests, a pyramid or 3D-polygonal shape, separated by thin glazing bars. Again, they can make an unusual and striking feature and can make a room feel more spacious. As with a curved skylight, rainwater should run off easily. Lantern and pyramid roof lights tend to be more expensive than flat skylights; the cost will be determined by the design, the materials and type of glass, and whether they open.

Curious about what you mind spend on double glazing for your roof windows? Read our guide on double glazing costs for all the information you'll need.

Manual, electric or solar?

Manual windows, opened either by hand or using a pole, are a less expensive option than electric windows – and you can still open them if the motor fails or there’s a power cut.

Electric windows, operated either by a switch on the wall or remote control, can be opened and closed with minimal effort – very useful for windows which are hard to reach, or if you’re not very mobile. They can often be programmed to close automatically when they sense rain or wind, to open when they detect fire, or to open and close according to a timer or thermostat. You can get electronic blinds too, which you can programme to open and close while you’re on holiday so it looks like you’re at home.

Solar-powered windows are powered by a solar cell on the outside of the window, instead of an electrical motor – so there’s no electrical wiring and no running costs. You shouldn’t need a backup system either, as the battery should recharge whenever there is daylight and be able to store power for days.

Dormer windows are vertical windows that sit in a sloping roof that has a mini roof of its own; this is usually the result of a loft extension. Dormer windows can look very attractive in both traditional houses and new builds, as long as they are not too large and in keeping with the style of the main roof, and can make a room with a sloping ceiling feel more spacious and less confining. Like the windows in the rest of your house, they can open in a variety of ways (sash, casement etc).

Conservation windows: if you live in a conservation area or a listed building, you may need planning permission for new roof windows, and they may have to be ‘conservation windows’ –windows specially designed to look traditional and unobtrusive. Different councils have different requirements, but typically, conservation windows have dark, often metal, frames, glazing bars (bars which divide them into smaller panes to make them look more traditional), and do not protrude from the roof.

Combination windows: as the name suggests, this refers to several windows grouped together.

Conservatory roof windows: either an energy-efficient glass roof or a tiled roof with windows will help insulate your conservatory and stop it from turning into a greenhouse in the summer and an icebox in the winter. You can read more about conservatory roofs here.

Balcony windows: these are the showstopper of the roof window family. They look like a normal window when closed, but whereas the top-hung top half opens out normally, the bottom section unfolds into a glass balcony with railings at the side. You can’t actually go out onto it – it’s like a Juliet balcony (without the double doors) – but it does create a very striking feature, let a huge amount of light and fresh air in and offer excellent, panoramic views.


Roof window costs and sizes

Roof windows come in several dozen standard sizes, usually from 55cm x 70cm to 134cm x 160cm. This is not to say that smaller or larger windows are not available; often, companies will work with you to design your own roof lights exactly as you want them, meaning costs will vary.

Velux is the biggest and most well-known roof windows manufacturer. Here are some rough prices for its popular rooflights, which include the windows themselves plus installation:

Type of Window
Fixed flat rooflight
60cm x 60cm
Fixed flat rooflight
100cm x 150cm
Opening flat rooflight
60cm x 60cm
Opening flat rooflight
100cm x 150cm
Opening curved rooflight
60cm x 60cm
Opening curved rooflight
100cm x 150cm


A dormer window is likely to cost more than a flat roof light, as it involves more work. You’re looking at a price range of £600 to £1,250 for dormer windows, with an average price of £925 across the UK.

Here are some guide costs for replacing a pine-framed, centrepivoted manually opening window:

Small (66cm x 98cm)
Greater London
£900 to £1,050
Small (66cm x 98cm)
South and Midlands
£775 to £975
Small (66cm x 98cm)
£750 to £875
Large (134cm x 160cm)
Greater London
£1,300 to £1,350
Large (134cm x 160cm)
South and Midlands
£1,275 to £1,375
Large (134cm x 160cm)

The best way to get an accurate quote for your home is to let us put you in touch with leading UK suppliers of roof windows. Just hit the button below to complete our quick form.

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Types of roof window openings

Centrepivot windows open by being rotated horizontally through 180 degrees, which has the big advantage of meaning you can clean both sides easily from inside the room – after all, clambering up on the roof to clean them is probably not a task you want to undertake. Top third windows are similar, but the hinge is higher, so less of the window comes into the room when you open it, which goes some way to solving these issues.

Top-hung windows open outwards from a hinge at the top, without the window entering the room, which solves the problems above. You can get top-hung windows with a centre pivot too to allow you to clean them from the inside. Sidehung windows, as the name suggests, open from the side.

Means-of-escape windows: building regulations in England state that people must be able to get out of a room safely if there is a fire – and this may be through a window that fits the criteria for a ‘means of escape’. Means-of-escape windows must be accessible by a ladder if they’re not at ground level, have an opening of at least 45cm x 75cm, and be able to stay open without someone holding them. Because a centre-pivot window is divided into 2 when it opens, a top-hung or side-hung window is more likely to be suitable.


Roof window frames and materials

You can choose to have the frames for your roof windows made from uPVC, wood or metal.

uPVC, a type of plastic, has many advantages despite usually being the least expensive option: it’s durable, sturdy, a good insulator and low-maintenance, as it won’t rot or rust and can just be wiped clean. Because it’s water resistant, it’s particularly good for kitchens and bathrooms. But not everyone likes the look of uPVC, particularly on older buildings, and in a listed building or conservation area it may not be allowed.

Wood looks more traditional, and for that reason alone many people prefer it, even though it’s usually more expensive than uPVC and more high-maintenance. The latter is more of an issue with roof windows than with those elsewhere in the house, as accessing them can be difficult and even dangerous. If taken care of, however, wood can last longer than uPVC.

Aluminium’s big asset is that it is strong and lightweight, so aluminium frames are usually very slim, allowing a lot of light into your home and giving the frames an elegant look. It is also low-maintenance – aluminium can’t rot or rust and is easy to clean – and durable; it should also last longer than uPVC.

Steel frames, again, are strong, slim and lightweight; and because of its traditional look (cast iron roof lights became popular in the Victorian era), steel is often preferred, and sometimes required, for conservation roof lights. Steel rusts but can be galvanised to prevent this.

As with ordinary windows, you don’t have to have the same frame inside and outside – so for example, if you like the natural look of timber, you could have a metal or uPVC frame outside but a timber frame inside, so you get the style you want inside your home while avoiding the worst of the maintenance.

Check out our windows guide to discover more about the different types of windows available.


Glass, glazing, and insulation

Think all you want from the glass in your roof light is to be able to see through it? Think again. Different glazing options will allow you to save energy, tighten security and increase your privacy – or possibly all 3.



Double glazing has many benefits. It reduces the heat lost through your window – roof windows are even more prone to heat loss than the windows in the rest of your house because hot air rises – and therefore the money you have to spend on heating. It reduces the noise that comes in from outside; it reduces condensation, which can lead to mould; and it makes the window more secure.

Triple glazing has 3 sheets of glass instead of 2, so all the benefits above are intensified – but it is more expensive, is heavier, and may reduce the amount of daylight coming in.

Low-emissivity or low-e glass further improves insulation, as it has a coating which reflects heat back into your room.


Safety and security

Toughened safety glass has been heat treated so that if it breaks, it does so into small, usually blunt-edged fragments which are less dangerous than large shards.

Laminated glass has a layer of plastic between the 2 panes of glass, which the 2 panes are stuck to – so if it is smashed, the glass doesn’t fall apart, but stays in place stuck to the plastic until you can get it fixed. Laminated glass will also help keep out noise.



Self-cleaning glass has a coating that reacts with sunlight to break down dirt, and makes rainwater spread more evenly over the glass so the dirt is washed away more effectively. Unless you can open them and clean them from inside, cleaning is likely to be more of an issue for roof windows than for those elsewhere in the house, given how hard they can be to reach.



Frosted or obscure glass is good for bathrooms and other rooms where privacy is important, as it is embossed with a pattern which lets light through, but doesn’t allow things to be seen with any clarity.

Tinted glass helps both with privacy and with keeping rooms cool, because it reduces the amount of sunlight that comes in – helping with solar glare too. Of course, this does mean the room won’t be as light and bright as with clear glass. Tinted glass comes in a range of colours, including blue, brown, grey and green.


Roof window brands and manufacturers



Fakro is the world’s second-biggest roof window manufacturer, with around 15% of the global market. The company was established in 1991 in Nowy Sacz, Poland, and has its UK head office in Swadlincote, Derbyshire. The company has twice been a winner of Poland’s Economy Award, most recently in 2011.



Keylite has won numerous awards, the most recent innovation of the year in the 2018 Construction News Specialists Awards, construction product of the year in the 2017 Irish Construction Industry Awards, and best brand new product in the 2017 Housebuilder Product Awards. Its UK head offices are in Swadlincote and Cookstown, County Tyrone.



So well known that its name is often used synonymously with roof windows, the international VELUX Group, which has its headquarters in Denmark, operates in more than 35 countries and employs 10,200 people worldwide. The company was established in 1941 in Denmark, and expanded into the UK in 1954; its UK head office is in Glenrothes.


To discover how much roof windows would cost for your home from one of these leading manufacturers, just complete this form.

Written by:
Fran is The Eco Experts' resident solar panel and double glazing oracle She loves orangutans and is passionate about protecting the planet's rainforests from the unsustainable production of palm oil. And minstrels.
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