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ThermalHEART is the technology stitched in to the core of specialist APL window and door profiles to minimise the transfer of cold.

There is a ThermalHEART insulator in every profile, which is made from polyamide nylon, providing an excellent thermal break. It separates the inside and outside metal faces, meaning the transmission of cold is dramatically reduced. When combined with double-glazing, the result is a window with the market’s most advanced barrier system.

Typically, ThermalHEART windows offer around 35 per cent better thermal performance over and above standard double-glazed windows. This technology is available in APL’s mainstream residential window brands, as well as in the Metro series.

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