Warmcore aluminium bi-fold doors

Concertina sliding doors, with thermal cleverness built-in.

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Aluminium, with something special up its sleeve

The Warmcore aluminium folding sliding door system does something quite special, keeping your home warmer than the standard alternative. Its technical design is based around a high-performing thermal core, meaning its streamlined good-looks work hard to keep your home warm. A standard double glazed option can achieve a U-value of 1.5 W/m2K, with 1.0 W/m2k achievable with 44mm triple glazing. That’s impressive stuff.

It looks great on the outside, but something radical is going on inside. With slim sight lines, energy efficiency, effortless rollers and unbeatable weathertightness, it’s an innovative way to transform your home, without compromise.

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Our guarantee

We’re not just backed by our customer’s recommendations. Our products are made to the highest standards.

We’re also backed by a 10-year manufacturer’s guarantee. We’ll cover the cost of any necessary replacement if the damage isn’t your fault. Because if you’re not happy, we’re not happy.

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Happiness is about getting the colour just right

Sometimes, it’s what’s on the outside that counts.

That’s why we offer a wide range of colour choices. Alongside our standard colours, we also do a wide range of custom ones. Our online quoting tool guides you through a range of options or you can speak to us about choosing your own – we’d love to help.


Let's talk technical

The beauty of WarmCore is in the details:

  • Triple-sealed door leaves eradicate draughts
  • Bespoke union mouldings for gaskets
  • PAS24 and Secure by Design compatible
  • Flexible threshold options
  • Strength and security approved by UKAS laboratory testing
  • Double-strength sash corners
  • Custom-engineered extruded aluminium hinges
  • ERA Five Star Guaranteed
  • Innovative clip-in bead design
  • 4 colours available – white, grey cream and black.

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