Education - Thermal Break

What is Thermal Break?

A thermal break is a component within a door or window frame that interrupts the direct path of heat transfer between the interior and exterior faces of the frame. In steel doors and windows, the frame material itself conducts heat very efficiently, which means that without any interruption, heat can move freely from the warm side of the frame to the cold side. A thermal break is typically made from a low-conductivity material, such as polyamide or polyurethane, and is inserted between the interior and exterior steel sections so that they are no longer directly connected.

By separating the two sides of the frame, a thermal break reduces what is known as thermal bridging, the process by which heat travels quickly through a highly conductive material and bypasses the insulating properties of the rest of the system. Without a thermal break, steel framing can transfer heat rapidly enough to reduce overall energy performance, increase condensation risk on interior surfaces, and make a building less comfortable near doors and windows. Thermal break construction directly addresses this by keeping the conductive steel components isolated from each other, allowing insulation to function more effectively across the whole assembly.

The result is a frame system that performs significantly better in terms of energy efficiency compared to non-thermally broken alternatives, though the overall performance of any given door or window still depends on additional factors like glazing type, frame design, and overall system configuration. Thermal break technology is now a standard feature in higher-performance steel door and window systems, particularly in climates with significant temperature swings, where reducing heat transfer through the frame has a meaningful impact on comfort and energy costs.