What a thermal break actually is, how it works, and why it makes a real difference to your energy bills and comfort — explained in plain English.
Aluminium is an excellent conductor — great for strength and slim sightlines, but it also conducts heat and cold straight through a frame, from outside to in and back again. A thermal break interrupts that path.
It's a strip of low-conductivity material — typically a rigid polyamide — fitted between the outer and inner sections of the aluminium frame. The two halves of the frame are mechanically locked to this strip rather than joined directly to each other, so heat can no longer travel straight through the metal.
The result is a frame that still has all the strength and slim profile of aluminium, but behaves far more like an insulator where it matters most.
A thermal break isn't just a technical detail — it changes how a room actually feels, day to day.
Less heat escapes in winter and less heat gets in during summer, so your heating and cooling doesn't have to work as hard to keep up.
Non-broken aluminium frames get cold enough to sweat on the inside face in winter. A thermal break keeps the inner frame closer to room temperature, so moisture has far less chance to form.
No more cold radiating off the window frame in winter or a hot frame to the touch in summer — just a more even, comfortable room temperature near your doors and windows.
Breaking the direct metal-to-metal path also reduces how easily sound vibrates through the frame, for a noticeably quieter room — especially paired with double glazing.
You keep every bit of aluminium's strength and slimline look — the thermal break sits inside the profile, invisible from both sides once installed.
In Australia, window and door energy performance is measured through WERS (the Window Energy Rating Scheme). Thermally broken frames are one of the biggest single factors in a stronger rating.
A quick guide to the terms you'll hear when we talk through your quote.
Thermal break refers to the frame itself. Double glazing refers to the glass — two panes with a sealed air or gas gap between them. The two work together: a thermally broken frame stops heat moving through the aluminium, while double glazing stops it moving through the glass. For the best result, you want both.
U-Value is the measurement used to describe how much heat a window or door lets through — the lower the number, the better the insulation. WERS (Window Energy Rating Scheme) is the independent Australian rating system that publishes these figures so you can compare products on a level playing field.
Every Moonlight door and window can be specified with a thermally broken frame — tell us about your project and we'll talk you through the options.