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aluminium casement windows house

Here at Colin’s Sash Windows we are not only the UK’s biggest supplier of sash windows – we sell a lot of aluminium windows and aluminium doors. Why? Well, our prices are really competitive and, more importantly, our after sales service is second to none. We select who to work with very carefully as our reputation is at stake.

We’ve chosen Smart Systems which is the UK’s biggest supplier of aluminium doors and windows.

They have a very good range of aluminium casement windows. Our biggest seller is the Alitherm Heritage aluminium windows system because we sell a lot of Heritage steel replacement French doors in this range so you can match your windows and door. Inspired by the aesthetics of traditional Steel windows, Alitherm Heritage features signature slim sightlines and attractive contours making it the ideal choice for heritage building conservation areas where building regulations demand a like-for-like replacement.

We have another option for slimline aluminium windows – our Smart Alitherm 300 range. This option is slightly cheaper than the Alitherm Heritage range. We also offer aluminium flush casement windows – these are the Alitherm 500. A top quality side hung or top hung system.

Our aluminium double glazed windows are suitable for domestic or commercial applications as replacement windows for existing building, and for installations into new buildings. Aluminium casement windows offer strength and durability and don`t rust. The aluminium window frames utilise an innovative polyamide thermal break technology, which creates a barrier between the cold air outside and the warm air inside providing high thermal efficiency. Aluminium casement windows are a top choice for many households because of their sturdiness and low maintenance needs. With toughened glass they provide extra security and peace of mind. They can greatly reduce the noise that is coming from outside and give you a peaceful home.

  • Modern, contemporary style windows
  • Very slim sight lines
  • Ease of maintenance
  • “A” energy rated as standard
  • 10 Year Guarantee
  • Secure locking hardware
  • PAS 24 Security Upgrade available
  • Wide range of RAL colour options available including dual colour. Black aluminium windows being the most popular
  • We also offer triple glazed aluminium windows
Aluminium Flush Casement Window

Standard colours: White, Grey, Black

Another benefit of our aluminium windows is the ability for them to be coloured in any of over 200 different RAL colours.

Specify dual colour if you want to enjoy the brightness of white on the inside frame faces and a striking colour finish on the outside.

  • Aluminium casement window colour RAL 9010
    RAL 9010
  • Aluminium casement window colour RAL 9006
    RAL 9006
  • Aluminium casement window colour RAL 9007
    RAL 9007
  • Aluminium casement window colour RAL 9005
    RAL 9005
  • Aluminium casement window colour RAL 7016
    RAL 7016
  • Aluminium casement window colour RAL 9001
    RAL 9001
  • Aluminium casement window colour RAL 6009
    RAL 6009
  • Aluminium casement window colour RAL 5001
    RAL 5001
  • Aluminium casement window colour RAL 3004
    RAL 3004
  • Aluminium casement window colour RAL 1015
    RAL 1015
  • White furniture
  • Satin furniture
  • Chrome furniture
  • Gold furniture

Handle colour options in White, Gold, Chrome, Black, Satin Silver

Multi-point locking system

The handle is supplied as standard with a key locking facility, however should you opt to have a fire escape opening hinge then the handle will be non-locking as standard. Utilising a multipoint locking mechanism, internal key locking handles and internal beads the window system offers the highest level of security as standard.

PAS 24 Security Upgrade

Our aluminium windows come with the option to upgrade the security to our PAS 24:2016 security package. PAS 24 is a set standard with specifications as to which our aluminium windows have been tested against. The PAS 24 upgrade includes hinge protectors and anti lifting blocks. The upgrade is generally mandatory on new-build projects.


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