Thermal breaks mean large aluminium windows don’t equal cold rooms

Remember aluminium windows from the 1970s? Insubstantial-looking windows in a timber surround that were plagued by condensation and did little to prevent heat leaving a room? Thankfully, glazing technology has come on leaps and bounds since for panoramic windows.

Modern aluminium windows offer great thermal ratings – known as ‘U’ values – and prevent heat being lost through the frame. It’s all down to a section of the frame called the ‘thermal break’ which is sandwiched between the exterior and interior aluminium parts of the frame (it’s the dark grey piece in the picture).

The polyamide material used for the thermal break is itself a very good insulator, and the clever multi-chambered design keeps heat transfer across the frame to a minimum.