The Alitherm Heritage door is the ideal replacement for steel balcony doors on heritage applications such as building renovations or apartment conversions. The Alitherm Hertitage door provides the solution for conservation areas where planning regulations require a like-for-like product replacement. Alitherm Heritage door profiles feature the systems signature slim sightlines and elegant lines that complement Smarts existing Alitherm Heritage window and mimic those of steel doors. The system has all the advantages of modern aluminium profiles that feature polyamide thermal breaks, allowing the system to achieve a U value of 1.5 when installed with a suitable sealed unit.