Bring the light in - how roof windows can transform your home

VELUX before and after

Whether you're building a kitchen, dining room extension or adding another bedroom to a loft conversion – it’s pretty easy to overlook the importance of getting enough daylight into your design. VELUX asked Mumsnetters for their top questions regarding natural light, roof windows and more.

Read on to find out our answers by VELUX daylight expert Grant Sneddon and enter the competition to win a £250 John Lewis voucher.

I've got a Victorian cottage, which we're adding an extension to. We want to retain the 'old and cosy' character, but ensure there is plenty of light. How do we get the right balance?

LITTLE BOY ROOF WINDOWS When planning your extension, maximising daylight should be high on your list of priorities, so choosing the right size and number of roof windows is hugely important. To bring in the perfect amount of natural light to the space, we recommend that your roof windows should make up the equivalent of 15-20% of the room’s floor space.

Don’t fall into the trap of placing roof windows above doors and adjacent to other windows to maintain neat symmetry in your plans. Pay attention to the areas in the centre of your extension, away from doors and windows. These are the most likely areas requiring daylight to lighten the room and keep it feeling spacious and open. We recommend an even spread of roof windows that will bring in the maximum amount of daylight. For example, it might be better to fit two larger roof windows than three smaller ones. Watch our Twice the Daylight video to see the difference that daylight can make to your new space.

If you’re worried about maintaining the period features of your Victorian cottage, take a look at our range of conservation roof windows that blend into the roof of your home, maintaining that all-important period charm.

Would having roof windows in the ceiling make heating our home more expensive?

It is well known that heat rises, so it’s natural to assume that roof windows might result in a loss of heat and an increase in energy bills. However, this isn’t the case with VELUX roof windows, which all come with innovative ThermoTechnology™, saving both energy and money.

The high performance materials used in the construction of our roof windows provide excellent energy efficiency through enhanced insulation and an airtight seal, meaning you can enjoy natural daylight without any detrimental impact on room temperature.

There are two ways to maximise energy savings. The first is through our different glazing options that are all designed to capture the heat from the sun to reduce heating costs. You can read more about glazing options here but glazing 70 is a good start. The second is our range of blackout energy blinds designed to retain the heat of your room thanks to the aluminium honeycomb structure of the double-pleated blackout cloth, which improves window insulation by up to 25%.

I live in a listed building, we have an existing single storey lean-to extension and I would love to get natural light in as it’s very dark. A few houses in our neighbourhood have put heritage-style roof lights in. Do you make any classic style windows suitable for listed buildings/conservation areas?

If you want to install VELUX roof windows in your listed building or in a designated conservation area, you should check first with your local planning authority before carrying out any work.

We have a special range of conservation roof windows that are designed to blend seamlessly into the roof of your listed building. The sleek black finish with vertical centre glazing bar will flood your home with natural daylight and add a modern touch to your cute cottage, while keeping the classic feel of the listed building. Available in either centre-pivot or top-hung opening, all our conservation roof windows are energy efficient and come with all the features you’d expect in a standard VELUX roof window so you don’t have to compromise style over functionality.

However, the black finish featured on our conservation packages may not be required in your area. If that’s the case in your home town, then you can choose any roof window and add one or more conservation glazing bars in the corresponding size to keep the heritage feel of your home.

Do you need planning permission to replace an existing (small) skylight with a larger window? It's a loft conversion.

You don't usually need planning permission to install a roof window, especially when replacing an existing window of the same dimensions. Typically, you will only require roof window planning permission if you're making very visible changes to your property.

Replacing an old roof window can give your room a new lease of life – and it’s quick and easy to do. It’s the perfect opportunity to bring even more daylight into your space, and you’d be surprised how much brighter a room can be if you make your roof windows even slightly bigger. Or, if you add a second roof window alongside the one you are replacing you can get twice the amount of daylight into your room.

The same standard VELUX sizes are available and they can usually be replaced from inside the room without disrupting the current internal finish.

For a brighter, contemporary look we recommend switching pine roof windows for white ones. White roof windows reflect more light back into the room than darker surfaces. You can also replace your manual roof windows with VELUX INTEGRA® electric or solar roof windows, which are perfect for out-of-reach areas.

In loft conversions, you can also change centre-pivot for top-hung roof windows and enjoy uninterrupted views.

The benefits of replacing your old VELUX roof windows are:

  • Improved insulation to make your room more energy efficient
  • Can be replaced from inside the room without disrupting the current internal finish
  • Same standard VELUX sizes available but with bigger glazed area, meaning more daylight in your home
  • Replaced in as little as four hours

Find the right replacement window for your home using our handy VELUX replacement tool.

The house we bought has two manual roof windows in the kitchen extension. How easy would it be to swap or upgrade them for the electric ones?

When your roof windows are out of reach we recommend VELUX INTEGRA®, our remotely controlled roof windows that you can open and close at the touch of a button, (no need for a long pole).

To upgrade your manual roof windows, it can be really simple. You can add a VELUX INTEGRA® solar conversion kit, which will allow your current VELUX roof windows to be controlled remotely by the power of sunlight. By going solar, you won’t have to do any re-wiring, which is required for our electrically operated roof windows.

One of the key features of the VELUX INTEGRA® range is they come fully equipped with a rain sensor, which will close your windows in the event of rain – perfect for when you’ve left them open during the school run and it starts to rain before you get home.

You can also add VELUX Active to your upgraded roof windows, where you can control them and their blinds from anywhere in the world via your smartphone. VELUX Active is a smart-home technology system that monitors the temperature, humidity and CO2 levels in your home and opens or closes your VELUX INTEGRA® roof windows, blinds and shutters to let more fresh air into your home. VELUX ACTIVE is also compatible with Apple HomeKit® and Siri.

We have roof windows in our kids’ bedrooms, but I’m always worried they will climb out through them. What’s the best way to make them secure?

Roof windows should be kept high enough up the sloped wall to be out of range for children. However, safety devices are available if this isn’t an option.

VELUX centre-pivot roof windows can be fitted with an opening restrictor, which prevents the window opening more than 100mm. The restrictor is removable so you can take it off to clean the window with a key when necessary.

Little girl windows

VELUX top-hung roof windows, which can be fitted with a lockable handle preventing them from being opened without the use of a key, is another option. But, if the window is required for means of escape in an emergency then a lockable handle should never be fitted.

Are there any advantages to VELUX over dormer windows? About to do a loft conversion and I’m a bit confused with the pros and cons.

With the cost of moving soaring, extending your home with a loft conversion is a great way to add space and value to your home.

Dormer windows and roof windows can be used in tandem, if your build allows, to create a bright, light and spacious loft conversion.

If you have a low roof you may be squeezed for enough headroom to make a comfortable conversion. If that’s the case a dormer will create more usable floor space and headroom within the property.

However, there are a number of reasons why choosing VELUX roof windows could be a better choice over dormers.

  • Roof window loft conversions can cost less than dormer loft conversions. If you already have enough usable head room, it makes it a far better investment option. On average, roof window loft conversions can start from around £15,000 (or around £1,150-£1,350 per square metre). In comparison, a basic dormer loft conversion usually costs from £20,000 (or around £1,250-£1,450 per square metre).
  • By adding roof windows you can also bring in more natural light for a bright and airy space and reduce reliance on artificial lighting.
  • VELUX roof windows can be fitted flush to the existing roof so that the dynamics and aesthetics of the exterior of your home aren’t altered.
  • Unlike a window on a dormer, you have a lot more flexibility when it comes to choosing the exact location of where you would like to install an opening roof window on your roof. This means that you can choose to add ventilation and daylight exactly where you need it most. VELUX top-hung roof windows open outwards, adding headspace to a room, and provide uninterrupted views.
  • Dormers are more likely to require planning permission as they can be considered to overlook a neighbour’s property. Roof windows are far less likely to require permission.

If you are struggling to visualise how your loft conversion could look with roof windows, try our free MyDaylight App. It lets you try out your renovation plans or design ideas before you start any work. It’s fun to use and shows how daylight can make your room seem bigger.

We would love to add windows to the roof but I worry that we could potentially be opening up our roof to a whole host of issues like leaking, messing with the electrics, etc. Is this not the case? And also, would you have skylights that open or stay closed?

There is still a historic misconception that a flat roof extension is more likely to leak, however, the products available have improved massively in recent years. Making a new opening in an existing roof and installing a flat roof window should be no problem for an experienced builder.

Placed high in the ceiling, flat roof windows will fill a kitchen extension with daylight and open up the space. Providing the perfect combination of natural light and fresh air, they also funnel steam, smoke and cooking odours out of your kitchen. For flat roofs, VELUX curved-glass rooflights in white polyurethane look as good inside as they do outside. The unique CurveTech dome lets rainwater easily drain off the surface, even on 0° pitched roofs, to let daylight shine through without raindrops getting in the way.

If you want an automated home with connected technology, sensors and remote-operated products, adding VELUX INTEGRA® electric roof windows and blinds and the VELUX ACTIVE indoor climate control starter kit would improve and simplify your life while making the indoor climate healthier and more comfortable.

What about condensation? We get it terribly in the autumn/winter with ordinary double glazed windows, would it not be a problem with windows in the roof?

Flat roof windows The external condensation you see on your vertical glazing during autumn and winter is actually a reflection of the high performance of your window. Your outside window pane should remain cold when the outdoor temperature drops, and as the air warms in the morning, condensation will form.

Condensation on the inside of your window is a different issue and relates to humidity levels in the home. However, there are ways to overcome this. A simple option is to ensure your room is properly ventilated throughout the day, which will allow any moisture in the air to escape.

But a clever way to avoid condensation on the inside of your windows is to consider the installation itself. At VELUX, we recommend splaying the lining opening, which essentially means that your window is not ‘boxed in’ from an internal perspective. This allows air to better pass over the glass and reduce condensation.

It is also important to consider other ways to prevent condensation in the home – simple things like avoiding drying clothes in the house or using lids on pots when cooking can dramatically cut down moisture in the air.

I have a kitchen extension that makes our dining room quite dark. I’d like a roof window in the extension but I’m concerned about the possible need to re-wire the kitchen lighting as well as knocking a hole in the roof! In your experience, how much is the overall cost of retrofitting a window to an existing roof?

Many people tend to rely on glass doors such as bi-fold and patio doors to bring daylight into their extensions. However, as extension doors tend to be further away from the original room, natural daylight – even on the brightest of days – can’t penetrate very far into the house. VELUX roof windows let in twice as much daylight as vertical windows because the glazing is angled directly towards the sun.

Where you install roof windows is just as important as the size and number you opt for. We recommend you consult an architect or builder to get their expert opinion on how to optimise the light in your extension.

Thought should be given to how and where daylight will enter and what direction the roof windows will face. Installing roof windows that face south will allow the majority of the day’s sunlight to enter the home, both naturally heating the home and letting the long summer evenings brighten up the room.

Our roof windows are available in a variety of different sizes, with three internal finishes to choose from, including a maintenance-free, white polyurethane finish for humid rooms such as kitchens. You can see our full selection here.

You can get a free quote from a VELUX certified installer in your area – all you have to do is fill in the details of your project here someone will be in touch.

Velux roof windows


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