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SL 38 aluminium windows

Slim Line 38 is a highly insulated system for inward and outward opening windows and doors, which combines elegance and comfort, with a unique design.

SL 38 Aluminium Windows

Reynaers SlimLine 38 windows have been designed to replicate the ‘steel look’ used in many traditional UK homes.


The SL 38 offers the highest levels of performance with excellent levels of security, weather resistance and thermal insulation.

With its slender look, SL 38 is the perfect window and door for modern homes as well as for the renovation of steel-frames, where respecting the original design is of utmost importance.

Warm and cosy

The SL 38 system is designed to offer class-leading insulation levels without compromising on the appearance of the window. The result is a window that will keep heat loss through the window to a minimum, withstand the worst that the British weather has to throw at it, and will help keep your energy bills down.


  • Industry-leading thermal insulation
  • Double or triple glazed options
  • Unique thermal profiles
  • U-value as low as 1.4 W/m2K

Safe and secure

Reynaers SL 38 windows and doors are designed and tested to the most stringent security standards. Knowing that the window has been awarded the Secured by Design accreditation means you can rest assured that your home, your family and your prized possessions are as safe as can be from would-be intruders.

  • One of the most secure windows available
  • PAS24
  • Secured by Design
  • Multi-point locking mechanism
  • Lockable handle

Sleek and elegant

With its minimalistic frame and ultra-slim profiles, Reynaers SL 38 combines elegant design and stability with market-leading energy efficiency. The SL 38 system is available in three very different minimalistic design variants, Classic, Ferro and Cubic; to perfectly match the architectural aspects of your home. These beautiful windows and doors can be provided with double or triple glazing without losing the ultra-slim look.


Tried and tested

SL 38 windows and doors have been designed by a highly experienced team of engineers at Reynaers’ purpose-built, world-class design and testing facility. As with all Reynaers products, this system has been put through the most stringent test regime, ensuring that it is one of the highest-performing and most reliable window and door system available.


  • Premium quality materials
  • Highest levels of performance
  • Industry-leading weather resistance

Endless design possibilities

All Reynaers windows and doors are made to meet your exact requirements. From the design of the window, to the colour of the frame and handle, there are almost unlimited options. When you choose Reynaers, you can make your windows and doors truly individual, a design statement to be proud of.

Performance

In combination with its superior insulation capabilities, the system provides the perfect harmony between durable material, clean design and reliability needed for your home. Renovation of steel-framed windows with modern, slim frame aluminium windows can also enhance the security, noise and energy efficiency of your property.


  • Ultra slim frame
  • Industry leading maximum sizes
  • Double- and triple-glazed options
  • Easy clean egress hinge option
  • Strong and durable
  • Secured by Design accreditation
  • U-value as low as 1.4W/m2K

Style Options

The SL 38 system is available in 3 different minimalistic design variants, Classic, Ferro and Cubic, to perfectly match the requirements of your project. The windows and doors can additionally be provided with double and triple glazing without losing the ultra-slim look.

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