Electric Opening Skylight 1200 x 1200mm Original price was: £ 3.336,00.Current price is: £ 3.236,00. incl. VAT
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Flat Roof Skylight 400 x 2000 mm Original price was: £ 657,00.Current price is: £ 468,00. incl. VAT

Flat Roof Skylight 400 x 1500 mm

Original price was: £ 515,00.Current price is: £ 404,00. incl. VAT

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Regal Glass Group: A trusted manufacturer of premium roof windows

Type: Fixed Frameless Flat Roof Skylight
Internal Size: 400 x 1500 mm
External Size: 600 x 1700 mm
Glazing Type: Triple Glazed
Net Weight: 34kg
U Value: 0.9 W/m²K
G Value: 58%
Light transmittance : τv [%] 72
Sound reduction (EN 12758): 39dB
UV transmission : τuv [%] 0

Experience the excellence of Regal Glass Group’s roof windows, featuring these impressive technical characteristics.

This item: Flat Roof Skylight 400 x 1500 mm
Original price was: £ 515,00.Current price is: £ 404,00. incl. VAT
Original price was: £ 515,00.Current price is: £ 404,00. incl. VAT
Original price was: £ 665,00.Current price is: £ 565,00. incl. VAT
£ 54,00 incl. VAT
£ 24,00 incl. VAT
£ 15,00 incl. VAT
£ 30,00 incl. VAT

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Easy Returns

Hassle-free returns within 30 days.

10 Year Warranty

Enjoy peace of mind with our extensive warranty.

Frameless Skylights Glass Performance

Experience the perfect blend of natural light, energy efficiency, noise reduction, and UV protection with our precision-engineered glass.

Modern Design
Solar energy transmittance (G value): g [%] 65
UV transmission : 0 τuv [%]
Light transmittance: τv [%] 72
Thermal transmittance (U value): : 0.9 [W/(m².K)]
Min 3.0 [W/(m².K)] / Max 0.1 [W/(m².K)] 70%
Shading coefficient: 0.66 SC
( Maximum SC 1.00 / Maximum SC 0.20 ) 42%
Sound Reduction: 39 dB (-2;-7)
( Maximum 40dB / Minimum 30dB ) 90%

Easy to replicate
Installation Guide

Dive into our user-friendly Installation Guide for a smooth skylight setup. Get the clarity you need, step-by-step.

Click below to explore the full guide.

Introducing the sleek Flat Roof Skylight 400 x 1500 mm from the esteemed Regal Glass Group, a masterpiece in the realm of skylight windows. This elongated skylight is designed to redefine flat roof spaces by maximizing natural light entry, ensuring your interiors are bathed in the rejuvenating glow of daylight.

Crafted with the latest triple-glazed technology, this skylight achieves superior thermal efficiency with an impressive U-value of 0.9 W/m²K. At its core, a 15-millimeter warm Edge spacer filled with Argon gas between each pane of glass significantly limits heat transfer, maintaining a consistent and comfortable indoor atmosphere year-round.

The true beauty of this skylight lies in its frameless design, which not only offers a sleek, contemporary look but also allows for unobstructed natural light to flood the space below. This minimalistic approach ensures that every ray of light is captured and utilized, brightening your interiors more effectively than ever before. Equipped with a self-cleaning mechanism, activated by sunlight, these skylights maintain their clarity and transparency with minimal maintenance, providing you with a clear view of the sky above without regular cleaning hassles.

This model is versatile, suitable for installation at pitches ranging from 6 degrees up to 45 degrees, allowing it to adapt to various architectural styles and requirements. Alongside enhancing the visual appeal of your space, it also offers sound reduction, UV protection, and is built with safety toughened glass to ensure durability and security.

Adhering to British Standards & Building Regulations, the Flat Roof Skylight 400 x 1500 mm is fully compliant, featuring all necessary Safety Markings and the CE mark, denoting its conformity with the highest EU quality and safety standards.

At Regal Glass Group, we understand the importance of choice and customization. That’s why, in addition to our range of standard size skylights that are readily available in stock, we proudly offer custom skylight solutions tailored to your unique requirements. Whether you’re enhancing a residential space or illuminating a commercial venue, our skylights are designed to bring light, elegance, and efficiency to any setting.


108 kg


205 × 10 × 145 cm


Regal Glass


Regal Glass Group Ltd

Internal Size

400 x 1500 mm

External Size

600 x 1700 mm

Glazing Type

Triple glazed

Glass Tint

Clear Tint



Roof Type

Flat Roof , Pitched Roof

Skylight Type


Top Glass Pane:

6 mm Planibel Clearlite / Thermally toughened

Air Gap

16 mm Argon 90%

Middle Glass Pane:

4 mm Planibel Clearlite Thermally toughened

Air Gap

16 mm Argon 90%

Bottom Glass Pane:

Stratobel Clearlite 44.2 with iplus 1.1 pos.5

Spacer Type

15mm Black Warm Edge

U value

0.9 [W/(m².K)]

Sound reduction - EN 12758

[dB] 39 (-2;-7)

Light transmittance: tv [%]


External light refection : ρv [%]


Internal light refection : ρvi [%]


Colour rendering index : Ra [%]


Solar energy transmittance : g [%]


Shading coefcient : SC




UV transmission : τuv [%]



5 reviews

5 reviews for Flat Roof Skylight 400 x 1500 mm

Clear filters
  1. Benjamin Stewart

    The bespoke skylight for our staircase from Regal Glass is simply breathtaking. Highly recommend! Plus London delivery was express!

  2. Adam Turner

    The light that floods in through our roof window has made our staircase a centerpiece in the home. Exceptional product!

  3. Amelia wilson

    The skylight in our small kitchen has made all the difference. It’s incredible how it opens up the space. Kudos to Regal Glass Group for their excellent work in Liverpool!

  4. Noah Brown

    The bespoke skylight we got for our bedroom has exceeded all our expectations. The quality and service from Regal Glass Group are outstanding.

  5. Henry Green

    The installation of a kitchen skylight has transformed our space. Cooking under the natural light has never been more enjoyable. Kudos to Regal Glass for their exceptional products and service.

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