Guides
Thermal Break Windows: What the Break Does
Hold a cut section in one hand and a good insulating unit in the other, and the weak point of a modern window becomes obvious. The glass is doing real work; the aluminium around it is a straight path for heat unless something breaks that path. A thermal break is the barrier that interrupts it. This guide explains what the break is, where heat escapes without it, when it earns its cost, and how to spot it on a section drawing before an order is placed.
What a thermal break is
A thermal break is a non-metal barrier set between the inner and outer faces of an aluminium section, so the two halves no longer touch. Aluminium conducts heat readily, and a frame with a continuous metal path carries heat straight from the warm face to the cold one. The break interrupts that path. It is usually a reinforced polyamide strip, crimped or rolled into the profile after extrusion, and it carries the same structural load as the metal around it.
Where heat crosses the frame
Heat leaves a window in three places: through the glass, around the edge of the unit, and through the frame. The glass is usually addressed first, with an insulating unit or a coating. Once the glass improves, the frame becomes the easier route for heat around the unit, which is why the break matters more after the glazing has been upgraded. Ask for the frame condition of the series before choosing an energy target.
When the break changes the result
The break earns its cost where a real temperature difference has to be held: cold winters, hot summers with heavy cooling, or a building that needs an energy figure for a code submission. In a mild climate with light heating and no air conditioning, a broken section changes running cost less, though the inner face stays warmer and condensation is less likely. Choose the section against the climate and the energy target.
Reading a break on a section drawing
Look for the point where the inner and outer walls stop being one piece of metal. A real break shows a continuous strip of non-metal separating the two faces, with no aluminium bridging the joint beside it. A section that steps in width but keeps the metal joined is a shape change. Check the strip where it meets the glazing line as well, because the break has to run past the glass edge.
Where Adam Alux uses the break
The aluminium is 6063-T5 across the range. In the facade lines, the opening unit profiles carry thermal break options, so a vent inside a curtain wall can be specified with the break where the vision bars have one. Across the window series the section drawing is the authority, so ask the drawing to show the break for the series you are buying rather than reading it from a family name.
Questions to put to a supplier
Put these questions in writing. Which sections in the quoted series carry a break, and what is the strip made of? Does the break run around the corners and past the glazing line, or stop at the straight length? Which items in the order are broken, and which are not? Where a project needs the break confirmed, the dimensional pack ships with the quotation and CAD is available on request. Ask for the answers on the drawing itself.
FAQ
Frequently asked
What is a thermal break window?
A window whose frame section carries a non-metal barrier between its inner and outer aluminium faces, so the two do not touch. The barrier, usually a reinforced polyamide strip, stops heat travelling straight through the frame. The glass is unchanged; the frame stops acting as a conductor between the outside and the room.
How much difference does a break make?
It depends on the climate and on the glazing. Once the glass is improved, the frame becomes the easier path for heat, so the break does more work. In a mild climate with light heating, the running cost effect is smaller, though the inner face stays warmer and condensation is less likely.
How do I tell a real break from a shape change?
Look for a continuous strip of non-metal between the inner and outer faces, with no aluminium joining them beside it. A section that changes width but keeps the metal joined across the joint is a profile change. Check the corner and the glazing line too, because the strip has to keep the path closed there.
Does every Adam Alux window series carry a break?
The section drawing is the authority for each series, and the alloy across the range is 6063-T5. In the facade lines, the opening unit profiles carry thermal break options. For a window series, ask the supplier to show the strip on the section for the series quoted instead of reading it from a family name.
What should I ask a supplier about breaks?
Which sections in the quoted series carry a break, what the strip is made of, and whether it runs around the corners and past the glazing line. Ask for the break shown on the section drawing for each item in the order, and check it against the pack that ships with the quotation.
Keep going
Related in the range
Send your opening schedule
Series, glazing and finish come back as one quotation, with the full dimensional pack on PDF and CAD on request.