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Aluminium Heritage

Alitherm Heritage Windows

Thin steel windows are still a popular idea in the UK, but improvements to building regulations over the years mean that it’s becoming more and more difficult to be approved for use. We believe the Heritage aluminium product offers a solution to this.

Thanks to a polyamide thermal break within the slim frame, the Alitherm Heritage can provide an overall Uw-value of 1.5 when paired with high-performance double glazing. The thermal break is 160x better than steel. Fantastic for renovations where a steel replacement in no longer an option, and perfect for stone mullions.

Aluminium Heritage build scaled
Aluminium Heritage in bright blue
Aluminium Heritage build 2
Aluminium Heritage build 3 scaled
Aluminium Heritage on stone building
Aluminium Heritage build 4

Full Details

In general, Alitherm Heritage provides us with a modern solution to a traditional steel window. Better thermal efficiency, no rust and a 40 year typical lifespan. There’s no need for re-painting, or any form of serious maintenance – simply wipe down with a warm, damp cloth.

To best achieve a thin a uniform heritage look, outward-opening casements and doors are the best way to go, although there is a slightly wider tilt-turn frame available too. Handles are black as standard, and there are many others to choose from if you require a more art-deco style, or perhaps a traditional monkey-tail. No matter which handle you choose, it will connect to a multi-point locking system within the frame. Both casements and fixed lights have been tested to PAS24.

Adding trickle vents for background ventilation are an option – either as an additional frame piece, or as an extra section inserted above the glass unit. If you experience a noticeable amount of humidity inside your home, we recommend fitting these.

Alitherm Heritage is especially useful for replacing windows within thin stone mullions. The incredibly slim 47mm frame depth is perfectly suited to these, and including an odd-leg (or z-section) forms a neat cover over a small part of the angled external section of a stone pillar.

Typical Lifespan40 years
Best U-Value1.5 W/m2K (using sealed unit 1.0 W/m2K)
FinishesSingle or dual colour, marine quality polyester powder coated aluminium as standard
GlazingDouble, Triple, Obscure, Laminated, Toughened
Maximum Sizes based on single openerSide Hung: Width 700mm x Height 1400mm
Top Hung: Width 1400mm x Height 1300mm
Maximum Weight40kg
Manufactured inUnited Kingdom
Frame Depth47mm
SecurityPas 24 Compliance on request
Performance and
Air: Class 4, 600Pa
Water: Class 9A, 600Pa
Wind: Class AE, 2400Pa
Opening Configurations

Fixed Frame

Fixed Frame Configuration

Side Guided

Side Guided Configuration

Top Guided

Top Guided Configuration

Chop Sample

Below are some of our recent galleries which include Alitherm Heritage