Key Features

Slimline System

Ultra-slim glazing, giving superb sightlines

High Performance

Outstanding thermal efficiency, with a u-value of 1.1 W/m2K

Innovative Design

Dual colour options, plus access to 200+ RAL colours

Strong & Secure

Heavy duty quadruple stainless steel rollers, assisting smooth sliding on bottom rail

Fitting Options

Two threshold options available for fitting – rebated or level threshold

Discreet Ventilation

Quadruple locking of intermediate vents.

AB-39 Slimline Bifold Door in Modern Home
  • Finishes & Materials
  • Thermal Efficiency
  • Accessories
  • Safety & Security
  • Technical/Downloads

Finishes & Materials

RAL Colour Picker


The AS-20 slimline sliding patio door is finished in a durable powder-coat paint. White, grey, and black are classic colour options while for a unique appearance you can offer your customers any of over 200 RAL colours. All powder-coat finishes are extremely low-maintenance and come with a 20-year guarantee.

Obsidian Black
Frost White
Velour White
Province Green
Antique Green
Amazon Green
Desert Grey
Olive Green
Platinum Grey
Antique Grey
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Aluminium & Materials

The AS-20 slimline sliding patio door uses only premium-quality aluminium. Aluminium is an inherently strong material which is weather-resistant and thermally-efficient. It is also extremely versatile and compatible with an endless array of product designs and specifications.

Thermal Efficiency

Bifold Doors Locking Mechanism

Thermal performance

The AS-20 slimline sliding patio door has been tested to ensure that it meets current building regulations for thermal performance. Our aluminium slimline sliding patio doors can help to:

  • Reduce heat loss
  • Protect against condensation
  • Enhance energy efficiency
  • Lower energy usage
  • Promote sustainability


Door Accessories


Our AS-20 slimline sliding patio door is available with a selection of hard-wearing and attractive accessories. When you want to offer your customers the best in bespoke customisation, it’s important to use the best accessories to complement your aluminium doors and windows. Our AS-20 slimline sliding patio door can be specified with the following accessories.

  • High strength Bogie rollers
  • Stainless steel track system
  • Choice of contemporary and traditional handles
  • Powerful door magnets
  • Low threshold options

Safety & Security

Bifold Close Up

Safety & security

Our AS-20 – Slimline Sliding Patio Door is designed with safety and security in mind. Alongside our anti-finger trap gaskets, our AS-20 – Slimline Sliding Patio Door provides the following protection.

  • High security multi-point locking systems
  • Strong and secure frames
  • Robust hinges
  • Heavy duty shoot bolts
  • Magnetic door keeps


Technical & downloads

Click on the links to download all the essential technical product documentation. Visit our download page to browse the technical details of all our aluminium doors and windows.

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AAA Guarantee Cover


AAA Cleaning Cover

Powder Coating Cleaning

Heritage Doors with side panels

Outstanding Thermal Efficiency

All Aston aluminium windows and doors are designed and manufactured at our state-of-the-art factory. We use only premium-quality aluminium which is inherently strong, weather-resistant and thermally-efficient. Using the latest cutting-edge machinery, we can fabricate a bespoke range of aluminium windows and doors for your next installation project. For customised casement windows, we can create a range of sizes and styles to suit both modern and more traditional installations.

Become An Aston Installer Today

Boost your business by becoming an Aston installer today. Gain access to all our premium aluminium products and offer your customers a smooth and efficient installation service on bespoke aluminium doors and windows.

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