For when you need modern, secure, thermally efficient windows without sacrificing the heritage and character of your traditional or period property.

This extremely versatile aluminium window system is an authentic and cost effective glazing solution with the aesthetics of traditional steel windows. Ideally suitable for a wide range of applications including heritage, listed, retro refurbishment and Art Deco projects.

With slim sight lines that create maximum glass areas the stepped frame profiles, glazing bar options and hardware choices offer a classic appearance with excellent thermal and operational performance.

With a range of dedicated system components Alitherm Heritage can be designed to easily accommodate external render and cladding finishes and can be effectively used as an appropriate alternative for contemporary applications that require slim sight lines

Exclusive to this system, Alitherm Heritage windows can be built as a series of individual modules to form a large multi part window coupled with a flush or feature drip bar.

A dedicated external door system with matching frame profiles and exclusive hardware is also available to compliment this window range.


Product Information

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.

All main profiles feature polyamide thermal break technology that enhances the thermal performance of the product, allowing Alitherm Heritage windows to achieve a window energy rating ‘A’ grade when fabricated with the correct specification and glazed unit. Profiles have a high quality powder coated paint finish at Smart’s state of the art paint facility in a choice of finishes, including single or dual colour, in a range of standard and non-standard colours.

Design Applications

Windows: fixed windows, side hung & top hung open out casement
Doors: single or double open out balcony doors


  • Window Energy Rating ‘A’ – when using correct profile, glass unit & spacer bar
  • 1.6 W/m²K with 1.2 centre pane U value
  • 1.4 W/m²K with 0.8 centre pane U value
  • Method of fabrication: corner crimping
  • Glazing options 24mm to 32mm (opening windows accept 24mm units only)
  • Gasket glazed
  • High security multi point locking
  • Traditional Art Deco handles available


Art Deco Heritage windows



Document Downloads

File Type Document Description Download Document
Adobe PDF Alitherm Heritage Brochure
Download (11.3 MB)
Adobe PDF Alitherm Products
Download (2.2 MB)
Adobe PDF Alitherm Heritage
Section identification Guide
Download (33.5 MB)
Adobe PDF Alitherm Heritage
Product Data Sheet IMS123AH.201410
Download (508 KB)
Adobe PDF Alitherm Heritage
Supply only – Guide to installation
Download (403kb)

Technical Specification


Product Type Windows and Doors
Material Aluminium Polyamide
Dual Colour
Thermally broken


Max width 900
max height 2100
Max weight 60
Thermal suitability ★★★★★
Min Glazing 24
Max glazing 32

Locking options


Building suitability

light duty