Flat roof windows with a sleek design


Our flat skylights with double or triple layered glass are the perfect combination of maximum light transmission, maximum thermal and sound insulation and a sleek design. They do not only look great, they also score high in every aspect.
Characteristic Skylux Vitria Skylux iWindow2 Skylux iWindow3
Price-quality Unparalleled Premium materials Premium materials
Glazing HR++ double glazing HR++ double glazing HR+++ triple glazing
Insulation value 1.1 W/m²K 1.0 W/m²K 0.5 W/m²K
Material White PVC frame Aluminium and PVC Aluminium and PVC
Installation Simple clips Fast clips Fast clips
Options Sunblind, blackout blind can be ordered separately Sunblind, blackout blind, LED lighting Sunblind, blackout blind, LED lighting
Opening system Manual or electric Electric Electric
Extra features Best price, easy installation Sleek design, superior insulation, larger sizes Sleek design, superior insulation, larger sizes, better sound insulation
Pice & details Discover Vitria Discover iWindow2 Discover iWindow3

A flat roof window for every project

For new constructions or complete refurbishments

Create the perfect atmosphere in your home thanks to the iWindow. Our flat roof windows offer maximum daylight, excellent insulation, and a sleek design. Enjoy plenty of daylight with comfort and style.

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For refurbishments without removing the existing curb

Upgrade your home with natural daylight without major demolition work: discover iWindow for refurbishment and preservation of your existing curb. Improved insulation, maximum daylight and a sleek design.

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Flat roof windows with a sleek design


Our flat roof windows with double or triple glazing are the perfect combination of maximum light transmission, maximum thermic and sound insulation and a sleek design. They do not only look great, they also excel in every aspect.

More than 85 sizes

iWindow is available in more than 85 sizes and different kinds of glass, including clear, opal and solar control glass. A perfect solution for every project. No compromises, only the best combination of dimensions and glass options. Discover the flexibility of iWindow and bring your vision to life.

Personalise your iWindow

In addition to double or triple glazing, we also offer accessories such as electric sunblinds, insect screens, and blackout blinds. Complete your iWindow with these useful additions.

Fixed or openable version

Discover the versatility of iWindow with both fixed and opening versions. Whether you are looking for a sleek fixed construction or the ability to let in fresh air. Choose iWindow and enjoy functionality and style in your space.

Flat roof window - Glass type Ug-value(W/m²K)
Insulation value
LT-value(%)
Light transmission
g-value(%)
Solar energy transmission
Rw-value(dB)
Acoustic value
Skylux iWindow2 Double glazing Clear HR ++ 1.00 W/m²K 75 % 52 % 39 dB
Skylux iWindow2 Double glazing Opal HR ++ 1.00 W/m²K 72 % 50 % 39 dB
Skylux iWindow2 Double glazing Solar control HR ++ 1.00 W/m²K 53 % 40 % 39 dB
Skylux iWindow3 Triple glazing Clear HR +++ 0.50 W/m²K 63 % 42 % 41 dB
Skylux iWindow3 Triple glazing Opal HR +++ 0.50 W/m²K 61 % 41 % 41 dB
Skylux iWindow3 Triple glazing Solar control HR +++ 0.50 W/m²K 46 % 33 % 41 dB

Choice of glass: clear, opal or solar control

Transparent clear glass

Clear or transparent glass is the traditional choice for many homeowners and businesses because of its classic beauty and clarity. It allows us to experience daylight in its purest form, contributing to a spacious and inviting atmosphere. At the same time, it provides a lovely outside view without disturbing elements.

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Opal glass

Opal glass offers the ideal balance between natural light and privacy. The milky white colour provides an even distribution of light, while limiting visibility from the outside. A popular choice for bathrooms and other spaces where privacy is important. Opal glass also helps reduce harsh shadows and glare from direct sunlight.

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Solar control glass

Designed to keep out the heat of the sun without sacrificing any daylight. This type of glass reflects the sun's rays and reduces heat transmission, keeping the interior cooler during hot summer days. There is no change in colour perception of the glass or perception of the interior space under the window.

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Enrich your home with the

Sleek design of the iWindow flat roof window

The iWindow flat roof window distinguishes itself with its contemporary and sleek design. The compact PVC frame and the aesthetic framing contribute to its modern appearance. This sleek design is a valuable addition to any modern home, giving your interior a stylish upgrade.

Experience the benefits of a

Flat roof window with a high insulation value

A Skylux flat roof window not only offers an aesthetic aspect, but also an impressive insulation value. With a U-value of up to 0.5 W/m²K for the H+++ glass and a sound reduction of 41 dB, you can enjoy excellent thermal and sound insulation. Furthermore, we offer a guarantee on an EPB-compliant solution, ensuring you an energy-efficient and environmentally friendly choice.

Enjoy up to 40% more daylight

Plenty of natural daylight

Our flat roof windows are always delivered with a straight curb, which means that the daylight surface entering through a 100x100 cm window is actually 1 m². Unlike competitors who use splayed curbs that provide a smaller daylight surface as the dimensions of the roof opening are larger than the actual daylight size. This means that you have to purchase a larger skylight from our competitors to get the same 1m² of natural daylight. Choose our flat roof windows and benefit from a maximum amount of natural light in your home.

Upgrade your skylight

Replace your old skylight without changing the curb!

This solution is perfect if you only want to replace your old skylight without changing the existing curb. With our fixed design and convenient hinge system, you can easily attach the glass frame (iWindow2, iWindow3, or iDome) to a chosen curb. Fast, easy, and cost-effective!

Testimonial - Firma Cloet

Discover the perfect combination of maximum daylight, excellent thermal and sound insulation and stunning sleek design. Thanks to the iwindow2 flat roof windows, you no longer have to compromise. Our flat skylights with double or triple glazing not only offer breathtaking aesthetics but also excel in all aspects. Experience the ultimate harmony between functionality and beauty. Choose the iWindow2 flat roof windows and discover how incredibly well they perform.

Discover the versatile iWindow2 roof window for every project


The perfect choice for new constructions and refurbishmens: iWindow2 roof windows offer innovation, style, and functionality.

For new constructions or complete refurbishments - fixed version

Bring natural daylight into your new construction project with the iWindow2 fixed version. Enjoy a radiant home with this fixed skylight.

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For new constructions or complete refurbishments - openable version

Improve ventilation in your new building with the openable iWindow2. Enjoy fresh air ventilation and a modern look.

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For refurbishments without removing the existing curb - fixed version

Upgrade your renovation project with the iWindow2 fixed version. Give your home a new dimension by replacing that old plastic skylight.

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For refurbishments without removing the existing curb - openable version

Optimise the airflow with the iWindow2 Flex. The Flex fits on the existing curb thanks to the built-in opening system.

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Discover iWindow3: extremely insulated flat roof window for passive houses


Experience an even better insulation and energy efficiency with iWindow3. Thanks to its HR+++ glass and an impressive U-value of only 0.5 W/m²K, the iWindow3 meets the strict requirements needed passive houses. Enjoy a comfortable and sustainable living environment with iWindow3 flat roof windows.

Full control and functionality thanks to our iWindow accessories


Complete your iWindow experience with our accessories. Exterior sunblinds, interior sunblinds, blackout blinds or electric insect screens - we offer various options to meet your needs. Enjoy ultimate control, functionality, and comfort in combination with your iWindow.

Interior sunblind

Create a cosy atmosphere and regulate the amount of daylight with our stylish interior sunblinds, specially designed for iWindow windows.

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Elektrisch Screen 40x40cm

Blackout blind

Enjoy a good night's sleep or create a perfect environment for audiovisual presentations with our blackout blinds for iWindow windows.

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Insectengaas kopen

Insect screen

Say goodbye to annoying insects and enjoy fresh air without any worries. Our electric insect screens offer easy and effective protection.

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Exterior sunblind

Protect yourself againts the bright sun and maintain a comfortable temperature inside with our exterior sunblind flat roof windows.

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