CS 77 Aluminium Windows and Doors

CS 77 is a thermally-broken, multi-chambered system for windows and doors that offers excellent levels of security, weather resistance and thermal insulation.

The CS 77 system offers a comprehensive range of inward- and outward-opening window and door designs that are available in a range of three different styles, making it ideal for both traditional and contemporary building designs.

Combined with a huge choice of colours and finishes, and the ability to specify a different colour inside and out, the CS 77 is a truly versatile system that can be specified to compliment almost any home.

The fibreglass-reinforced polyamide strips and weather gaskets are designed with ribs and hollow chambers to achieve superior thermal insulation levels. A variant of the CS 77 has been awarded the coveted Swiss Minergie accreditation.

  • Features
  • Style options
  • Downloads
  • Technical information
  • Opening options
  • Energy Efficiency


The CS 77 not only looks stylish but is also a great all-round performer in terms of thermal insulation, weather resistance and security:

  • U-values as low as 1.6W/m2K for doors and 1.5W/m2K for High Insulation Windows
  • Up to 600 Pa air-tightness
  • Up to 900 Pa water-tightness
  • Up to 2000 Pa wind load resistance
  • Accredited with UK Secured By Design security rating, and PAS 24:2016, as well as RC2 and even RC3 security ratings



Min. Visible width frame: inward opening

51 mm

Min. Visible width frame-vent: inward opening

89 mm

Min. Visible width frame: outward opening

17.5 mm

Min. Visible width frame-vent: outward opening

93.5 mm

Min. Visible width T-profile

76 mm

Max. height vent

2800 mm

Max. width vent

1200 mm

Max. weight element

170 kg

Overall system depth frame

68 mm

Overall system depth vent

77 mm

Rebate height

25 mm

Min. Glass thickness

4 mm

Max. Glass thickness

52 mm

Min. Glass thickness vent

4 mm

Max. Glass thickness vent

63 mm



  • Air tightness max. test pressure

    4 (600 Pa)

  • Water tightness

    9A (600 Pa)

  • Wind load resistance

    C3 (1200 Pa)


  • Burglar resistance

    PAS24, RC2/WK2, RC3/WK3


  • Thermal insulation (Uf)

    1.5 W/m²K

Opening options


Inward opening

Outward opening


Style options

The CS 77 window and door system is available in three different style options. Whether you prefer the more traditional Renaissance style or the very clean and contemporary lines of the hidden vent style, the CS 77 has the aesthetics to complement almost any home.


  • Functional

  • Renaissance


  • Hidden vent

Energy Efficiency



  • Thermal insulation (Uf)

    1.5 W/m²K

Visit our Energy Efficiency page for more information

Learn more

Visit our virtual showroom or find a Reynaers at Home local installer near you

You can now visit the Reynaers Showroom any time you like, with our brand new 360° showroom tour featuring our most popular products. We also have a network of local installers throughout the UK that can advise on product choice and installation for any of the Reynaers at Home aluminium systems for your home project.



Your style deserves to shine through, even in the smallest of details. That is why we offer over 900 RAL colours in various finishes to create the perfect final touch for your aluminium glazing. Combine your favourite colour with a metallic, anodised, matt, gloss, wood look or even a special low-maintenance and scratch-resistant coatex finish.

With an inspired range, you can choose from the latest colour trends as well as the timeless classics.