At AtoZ Design and Glass Ltd, based in London, we pride ourselves on supplying top-quality aluminium windows for both residential and commercial properties. Our range of Cortizo windows combines contemporary design with superior functionality, ensuring that your spaces are not only aesthetically pleasing but also energy-efficient and secure. Here are the six most popular aluminium windows that are widely used in London.

1. Casement Windows

Cortizo casement windows are designed with narrow sightlines and contemporary frames made from premium-grade aluminium, allowing for more glass surface and natural light. These windows offer excellent thermal and weather performance, making them ideal for both residential and trade markets, including refurbishment or new build projects. With a U-value of 1.3 W/m²K, these windows provide high thermal insulation due to multiple sealing levels. Available in side-hung and top-hung configurations, they come in a wide range of colors and finishes, including dual-color options. Additionally, these windows provide high security with PAS 24 certification and can achieve U-values as low as 1.0 W/m²K for superior insulation.

**Casement Frame by Cortizo**

» Glazing
Max. 44 mm
Min. 23 m» Opening possibilities

Outward opening
Side hung
Top hung
» Maximum sash dimensions
Slim sash (Side hung)
Width (L) 950 mm
Height (H) 1,300 mm
Slim sash (Top hung)
Width (L) 1,200 mm
Height (H) 1,300 mm
Heavy duty sash (Side hung)
Width (L) 750 mm
Height (H) 1,750 mm

2. Hidden Sash 80

The Hidden Sash 80 windows from Cortizo feature a sleek design with hidden hardware, maximizing the glass surface for better views and natural light. These windows provide outstanding thermal and acoustic insulation, with a U-value of 0.9 W/m²K when equipped with triple glazing. They are ideal for modern homes requiring top-notch energy efficiency and a minimalist aesthetic. The multi-chamber profiles ensure excellent thermal insulation, making these windows a preferred choice for energy-conscious homeowners.

**Cor Hidden Sash 80**

**» Glazing**
Max. 51 mm
Min. 36 mM
**» Opening possibilities**
Inward opening
Side hung
Tilt & turn
Tilt only
**» Maximum sash dimensions**
Standard Solution
Width (L) 1,300 mm Height (H) 2,400 mm
HD Hinges (Side Hung)
Width (L) 1,200 mm Height (H) 3,500 mm
» Maximum sash weight
160 kg

3. Hidden Sash 70

Cortizo's Hidden Sash 70 windows are characterized by slim profiles that increase the glass area, offering a U-value of 1.1 W/m²K with double glazing. These windows are perfect for contemporary designs, providing a minimalist look while ensuring high levels of energy efficiency and durability. The concealed hardware and a variety of finish options make these windows a popular choice for those looking to combine style with functionality.

**COR 70 Hidden Sash TB**

**» Glazing**
Max. 40 mm
Min. 26 mm
**» Opening possibilities**
Inward opening
Side hung
Tilt & turn
Tilt only
**» Sightlines**
Frame 70 mm
Sash 70 mm
**» Maximum sash dimensions**
Width (L) 1,300 mm
Height (H) 2,400 mm
HD Hinges (Side Hung)
Width (L) 1,200 mm
Height (H) 3,500 mm
» Maximum sash weight
160 kg

4. Hidden Sash 60

The Hidden Sash 60 windows feature an ultra-slim frame with a U-value of 1.2 W/m²K. They offer enhanced insulation properties and concealed hardware, making them ideal for smaller openings or areas where maximum glass visibility is desired without compromising performance. These windows also provide high security and a modern look, ensuring that your home remains stylish and safe.

**COR 60 Hidden Sash**

**» Glazing**
Max. 34 mm
Min. 16 mm
**» Opening possibilities**
Inward opening
Side hung
Tilt & turn
Bottom hung
**» Sightlines**
Frame 60 mm
Sash 60 mm
**» Maximum sash dimensions**
Width (L) 1,300 mm
Height (H) 2,400 mm
**» Maximum sash weight**
160 kg

5. 4600 Lift & Slide HI

The 4600 Lift & Slide HI windows from Cortizo provide superior insulation with a U-value of 0.8 W/m²K when using triple glazing. Designed for large openings, they offer a smooth sliding mechanism that allows for an effortless transition between indoor and outdoor spaces. These windows are perfect for creating expansive views and are highly energy-efficient, making them an excellent choice for homes seeking to blend indoor and outdoor living seamlessly.

**4600 Lift & Slide**

**»Opening possibilities**
Sliding of 2, 3, 4 & 6 sashes
Possibility of 1 rail (1 sash + 1 fixed light) & 3 rails
» Sections
Frame 160.6 mm - 3 rails 251 mm Sash 70 mm

**» Maximum dimensions/sash**
Width (L) = 3,300 mm
Height (H) = 3,300 mm
**» Maximum weight/sash 400 kg**

6. COR Galicia Alum-Timber TB

The COR Galicia Alum-Timber TB windows combine the warmth of timber with the durability of aluminium. They offer a U-value of 1.0 W/m²K, providing a stylish and high-performance solution that marries traditional aesthetics with modern functionality. These windows are ideal for projects requiring the natural beauty of wood on the interior and the strength of aluminium on the exterior, offering both visual appeal and robust performance.

ALU-Wood windows — **COR Galicia Alum-Timber TB**

**» Glazing**
Sash: Max. 40 mm, Min. 18 mm
Fixed light: Max. 30 mm, Min. 8 mm
**» Opening possibilities**
Inward opening
Side hung
Tilt & turn
Tilt & parallel
Bottom hung
**» Maximum sash dimensions**
Width (L) 1,400 mm
Height (H) 2,400 mm
**» Maximum sash weight**
100 kg

Best Choices and Best Selling Profiles

Best Choices:

4600 Lift & Slide HI: Ideal for large openings with superior insulation (U-value: 0.8 W/m²K), providing smooth sliding mechanisms and expansive views.
Hidden Sash 80: High thermal and acoustic insulation with a sleek, modern design, maximizing glass surface for better views and natural light.
Casement Windows: Versatile and highly efficient with options for side-hung and top-hung configurations, offering excellent security and energy efficiency.

Best Selling Profiles

Cortizo COR 70 Industrial: Known for its excellent thermal insulation, aesthetic appeal, and suitability for both residential and commercial applications.
Cortizo Casement: Popular for its versatility, narrow sightlines, and wide range of customizable options, making it a top choice for various projects.
Cortizo Sliding Systems (COR Vision and Lift & Slide): Highly sought after for their smooth operation, large glass panels, and superior insulation properties.

Conclusion

At AtoZ Design and Glass Ltd, we are dedicated to providing our clients with top-quality aluminium windows that meet the highest standards of design, functionality, and energy efficiency. Whether you are looking for windows for a new build or a refurbishment project, our range of Cortizo windows offers the perfect solution. Visit our website at www.atozdesignandglass.co.uk to learn more about our products and services.