I have a pitched roof
Roof window sizes for pitched and flat roofs
Did you know that daylight is more powerful from above, and that roof windows can provide 2 to 3 times more daylight than facade windows? If you want to reap all the benefits of bringing more natural light into your home with a roof window, it’s important to pick a size that’s tailored to the room’s size, layout, and purpose, as well as your particular roof type.
At VELUX, we offer a wide range of roof window sizes to suit all kinds of roofs and projects, whether you’re giving a tired loft a fresh new feel, adding light to a modern extension, or just making a small bathroom feel that little bit brighter.
VELUX roof windows don’t just open up your space; they open up new ways to enjoy it. From big, open-plan living areas to compact rooms that need a lift, there’s a size that fits. Not sure what you need yet? Let’s take a closer look at how to find the right roof window size for your home.
At VELUX, we offer a wide range of roof window sizes to suit all kinds of roofs and projects, whether you’re giving a tired loft a fresh new feel, adding light to a modern extension, or just making a small bathroom feel that little bit brighter.
VELUX roof windows don’t just open up your space; they open up new ways to enjoy it. From big, open-plan living areas to compact rooms that need a lift, there’s a size that fits. Not sure what you need yet? Let’s take a closer look at how to find the right roof window size for your home.
Get the size of your roof window right, and you’ll notice the difference
The size of your roof window plays a big part in how a room feels. Too small, and you might still find yourself switching the lights on. But get it right, and you’ll bring in just the right amount of daylight to make the space feel bigger, more open, comfortable, and a joy to spend time in.
In fact, 27% of homeowners* would have preferred a bigger roof window than the one they installed. And there are many good reasons for that. By inviting more natural light into the room, you can do great things for your general mood, as exposure to natural sunlight helps regular the body’s internal clock.
It’s not only about light, either, but also about the opportunity to open the room up to your outdoor space and the nature surrounding it. Furthermore, the right size window can help regulate temperature, reduce the need for artificial lighting, and make your home feel fresher and more energy-efficient overall.
*VELUX Combi Solution Study by NEPA, Dec 2019-Jan 2020.
Roof window size recommendations for pitched roofs
As a general guide, the window size should be around 15-20% of your room’s floor space if you have a pitched roof. If you already know that the roof window will be subject to shadows and obstruction from outside elements, such as neighboring buildings, a 25-30% roof window to floor ratio would be a good idea. It’s a simple rule of thumb, but it really helps when you want a room that looks good and feels even better. If you’re uncertain about what roof window size to go for, ask VELUX Advisory Service for a daylight analysis of your room.
Roof window size recommendations for flat roofs
For flat roof types with a pitch between 0° and 15°, the right window size can help you transform your space with stunning views and ample daylight, making your home feel larger and more open. The general recommended size for flat roofs generally should cover around 10-15% of the floor area. Flat roof windows are generally less affected by surrounding obstructions, such as neighbouring buildings or trees, than facade or pitched roof windows. This means they still bring in plenty of natural light even in tighter spaces. In cases where shadows are unavoidable, slightly larger windows can help ensure your room stays bright and airy.
Roof window size recommendations for low-pitched roofs
If your roof has a shallow pitch—between 10° and 20°—you’ll need a special low-pitch roof window. VELUX offers specially designed low-pitch roof window models to maintain excellent insulation, drainage, daylight intake, and add fresh air to your house extension, even when the roof angle is flatter than usual. Low-pitch windows are designed to let in more light than a vertical window, so you can achieve bright, airy spaces even with a smaller footprint. For low-pitch roof windows, we also generally recommend you aim for 15–20% of the room’s floor area — just as with roofs that have a broader pitch above 20°.
Choose your roof type for tailored guidance
I have a flat roof
Guide to roof window sizes for pitched roofs
Understanding VELUX roof window sizes
Choosing the right roof window for your pitched roof project is easy with VELUX. We offer a range of carefully selected sizes designed to fit a variety of homes and roof styles. Each window is labeled with a clear code, so you’ll always know the exact size you’re getting, making it simple to choose the perfect match for your needs or find a replacement for your older VELUX model.
Whether you’re looking to bring light into a cosy space or make a bold statement with expansive glazing and panoramic views, our sizes for pitched roofs cover it all. And if you're after even more daylight, a double window installation is a great way to fill your space with natural light and bring the beauty of the outdoors right into your home.
Here’s a guide to some of our pitched roof window sizes:
Size code and window size (width x height)
- FK06 - 66 cm x 118 cm
- MK04 - 78 cm x 98 cm
- MK06 - 78 cm x 118 cm
- MK08 - 78 cm x 140 cm
- PK06 - 94 cm x 118 cm
- PK08 - 94 cm x 140 cm
- SK06 - 114 cm x 118 cm
- SK08 - 114 cm x 140 cm
- UK04 - 134 cm x 98 cm
- UK08 - 134 cm x 140 cm
These sizes cover everything from compact spaces needing a little more light to larger rooms that benefit from floor-to-ceiling glazing and dramatic views of the outdoors. Often windows are combined into a double installation, to ensure an optimal daylight influx and a great view and connection to the outdoors.
(Note: This is a selection of some of our window roof sizes – more options are available)
Roof window sizes, endless flexibility
VELUX roof windows for pitched roofs provide a perfect solution for enhancing your space with endless possibilities. Whether you're working with a compact room or looking to create a dramatic feature, our roof window sizes suit a wide range of homes and projects.
You can combine multiple pitched roof window solutions to create a larger glass area and a panoramic view, or add fixed elements below your opening windows to create a stunning floor-to-ceiling effect. For ultimate flexibility, our pitched roof windows are available in manual, electric, and solar-powered options, giving you complete control over how you operate them.
To complete your setup, add interior blinds for light control or privacy, and choose exterior awning blinds or shutters for heat protection. If you want even more convenience, our smart controls, such as the VELUX App, allow you to manage your windows from anywhere.
Find the ideal pitched roof window size for your room type
Bedrooms and kids’ rooms
Bedrooms and kids’ rooms: Consider a double window with e.g. 2 x MK08 windows (2x78 cm x 140 cm) installed right next to each other. This option creates a light airy atmosphere and an amazing connection to nature outside. Plus, smaller rooms will feel an added spaciousness
Bathrooms
A single roof window can bring in increased natural light and control ventilation while maintaining privacy. For tranquility, go with a larger single window or duo combination to bring nature in. You can also add a moisture-resistant blind for extra privacy. As the bathroom is known for being a room with high humidity levels, it’s key to choose a VELUX roof window with a maintenance-free finish.
Living rooms
Go big! Combine a couple of PK08 (94 cm x 140 cm) or UK08 (134 cm x 140 cm) windows. Alternatively, go for our trio or quattro window combinations for a light-filled place with daylight, connection to the outside, and wow-factor.
Kitchens
A double or triple window combination above your worktops lets in both daylight and ventilation, making the space feel fresh and inviting. As kitchens often can become rather humid when you cook, a roof window with a maintenance-free finish is a must-have.
Home offices
A double window will make the room feel spacious and bring daylight right where you need it to help boost focus and productivity. For optimal indoor comfort and working conditions add an awning blind to maintain a comfortable room temperature or translucent blind for a flexible light dimming solution
Quick guide: How to choose your VELUX window size
- Measure your room: For pitched roof windows, aim for a window solution that covers 15-20% of your floor area. This will help maximize natural light while maintaining the balance of your room’s overall design.
- Think about usage: Choose larger windows or window combinations for main rooms like bedrooms, living rooms, or children’s rooms where you spend significant time. For less-used spaces, a more compact option is often sufficient.
- Consider the ways of operating the windows: You can upgrade your pitched roof windows to solar-powered or electric for extra comfort and convenience. Alternatively, you can go for manual operation if you prefer something simpler. If you want even more control, consider adding the VELUX App for smart home functionality.
- Further enhance your indoor climate: Pair your pitched roof windows with interior blinds to control light and privacy, and use exterior awning blinds or shutters to protect against heat. These options help you manage both light levels and temperature effectively.
Ready to find the right fit for your home?
At VELUX, we believe that more daylight, more fresh air, and better living starts with the right roof window – and that all begins with finding the right size.
Whether you're replacing an old window or starting a brand-new project, our roof window sizes give you the flexibility and choice to create the home you've always dreamed of.
Explore the full range of VELUX windows and discover just how easy it is to transform your space. Need a little help? Contact our team for expert advice, or check out our Design Advisory service to get personalised recommendations for your project.
Guide to roof window sizes for flat roofs
Understanding VELUX roof window sizes for flat roofs
With VELUX, finding the right roof window size for your flat roof is straightforward. Our flat roof windows are available in a range of sizes, designed to bring in as much light and fresh air as possible. Each window comes with a simple, easy-to-read code so you can be confident in your choice — whether it’s a replacement or a brand-new installation.
From smaller spaces that need extra light to larger hallways and other areas with limited access to natural light, our flat roof windows offer a smart, effective solution for illuminating any corner of your home.
From smaller spaces that need extra light to larger hallways and other areas with limited access to natural light, our flat roof windows offer a smart, effective solution for illuminating any corner of your home.
Here’s a quick guide to some of our roof window sizes for flat roofs:
Size code: Window size (width x height):
- 060060 - 60 cm x 60 cm
- 060090 - 60 cm x 90 cm
- 080080 - 80 cm x 80 cm
- 090090 - 90 cm x 90 cm
- 090120 - 90 cm x 120 cm
- 100100 - 100 cm x 100 cm
- 100120 - 100 cm x 120 cm
- 100150 - 100 cm x 150 cm
- 120120 - 120 cm x 120 cm
- 150150 - 150 cm x 150 cm
- 200100 - 200 cm x 100 cm
(Note: This is a selection of some of our flat roof window sizes – more options are available. For our regular and solar-powered glass rooflights, the size is shown with the long side first to indicate where the motor is mounted.)
How to find the size of your existing flat VELUX roof window
If you already have a VELUX flat roof window and need to replace it or find a matching model, you're in luck – it's simple to identify the right size. All VELUX roof windows produced since 1968 come with a data plate, making it easy to find the exact details you need.
For your VELUX flat roof window, just look for the size code (such as CFP 100150 or CVU 120120) on the type sign, which is located on the window sash. This code tells you exactly what you have, so you can choose a replacement that fits perfectly.
For your VELUX flat roof window, just look for the size code (such as CFP 100150 or CVU 120120) on the type sign, which is located on the window sash. This code tells you exactly what you have, so you can choose a replacement that fits perfectly.
Roof window sizes for flat roofs with endless possibilities
VELUX flat roof windows are the perfect way to flood your home with natural light, especially in spaces where traditional windows aren’t an option. Whether you're renovating or building a modern flat-roof home, our modular skylights can open up large areas of your roof to the sky, connecting your home directly with the outdoors.
If you're looking for flexibility, our solar-powered and electric flat roof windows let you enjoy natural light and fresh air with just a touch of a button. For spaces where access to natural light is the top priority, our fixed flat roof windows offer a sleek, uninterrupted flow of light without any need for operation.
Pair your flat roof windows with VELUX interior blinds for light control or privacy, and use anti-heat interior blinds to keep your home cool. For more convenience, the VELUX App Control lets you adjust your windows from anywhere, making it easy to manage natural light and ventilation.
If you're looking for flexibility, our solar-powered and electric flat roof windows let you enjoy natural light and fresh air with just a touch of a button. For spaces where access to natural light is the top priority, our fixed flat roof windows offer a sleek, uninterrupted flow of light without any need for operation.
Pair your flat roof windows with VELUX interior blinds for light control or privacy, and use anti-heat interior blinds to keep your home cool. For more convenience, the VELUX App Control lets you adjust your windows from anywhere, making it easy to manage natural light and ventilation.
Transforming every room in your flat-roof home
Just like our roof windows for pitched roofs, different spaces in your flat-roof home can benefit from a window size that’s tailored to the room:
Bedrooms and kids’ rooms
For bedrooms and children’s rooms, consider a flat roof window around 90 cm x 90 cm. This size brings in ample light and can also enhance airflow for improved sleep quality if you choose a vented, solar-powered, or electric roof window model. For larger rooms or loft spaces, combining two flat roof windows of 90 cm x 120 cm will further boost daylight and create a more spacious atmosphere.
Bathrooms
A 80 cm x 80 cm window is a great choice for bathrooms, offering plenty of natural light. To enjoy the added benefit of natural ventilation, choose one of our vented models to prevent moisture from building up, or our solar-powered or electric flat roof window options, which let you remotely open and close the window to let in fresh air when you want to. For larger bathrooms, a 90 cm x 120 cm flat roof window can ensure the space feels fresh and bright and really sells the feeling of getting ready or taking a bath right under the open sky.
Kitchens
For kitchens, where light and ventilation are key, a 90 cm x 120 cm or 100 cm x 150 cm flat roof window provides excellent daylight while keeping the room fresh. Larger vented roof windows or our solar-powered or electric options are particularly beneficial in kitchens that can become warm, as they offer natural temperature regulation and help get rid of moisture and unwanted cooking smells.
For the best use and effect of a flat roof window in your kitchen, consider slightly offsetting the window instead of placing it directly over your countertop to brighten your work areas without standing in your own shadow when cooking.
For the best use and effect of a flat roof window in your kitchen, consider slightly offsetting the window instead of placing it directly over your countertop to brighten your work areas without standing in your own shadow when cooking.
Living rooms
In living rooms, larger flat roof windows such as 200 cm x 60 cm or 200 cm x 100 cm provide generous light throughout the day and give you a front row view of the sky above - or perhaps a peek of the tree tops outside where you can follow the seasons change. Combining two 90 cm x 120 cm flat roof windows further enhances the connection to the outdoors, creating a stunning visual impact and a bright, welcoming living area.
Hallways/entryways
Hallways often benefit from larger flat roof windows or window combinations to create a brighter and more inviting entrance. Consider a 90 cm x 120 cm or 100 cm x 150 cm window for a significant increase in natural light. For even more impact, you can combine multiple windows to create a dramatic effect that floods the hallway with daylight, making it feel spacious, welcoming, and airy. Larger windows also help visually connect the interior with the outdoors, enhancing the overall ambiance of your home’s entrance.
Quick guide: How to choose your VELUX roof window for flat roofs
- Measure your room: For flat roof windows, aim for a window solution that covers 10-15% of your floor area. This is ideal for bringing in enough natural light without overexposing the space.
- Think about usage: Larger windows or modular skylights are great for areas like living rooms or kitchens where you want to create an open, airy feel. For smaller or less-used spaces, a more compact flat roof window may be a better fit.
- Consider the ways of operating the windows: Upgrade your flat roof windows to solar-powered or electric for added convenience and easy operation. If you prefer a low-maintenance solution, you can choose a fixed version for your flat roof windows. Adding the VELUX App will give you full smart control over your windows.
- Further enhance your indoor climate: For flat roof windows, interior blinds are available with options like semi-transparent fabrics, blackout fabrics, or anti-heat coatings. These options help you control light levels and maintain a comfortable indoor temperature throughout the year.
Ready to find the perfect fit for your flat roof home?
At VELUX, we believe that more daylight, fresh air, and better living start with choosing the right roof window – and that begins with finding the perfect size. Whether you’re replacing an old flat roof window or starting a new project, our roof window sizes for flat roofs give you the flexibility and options to make your home brighter and more inviting.
Explore the full range of VELUX roof windows for flat roofs and see how simple it is to enhance your space. If you need a little help, reach out to our team for expert advice or check out our Design Advisory service to get tailored recommendations for your flat roof window project.