In architecture and building construction a thermal break is an element of low thermal conductivity placed in an assembly to reduce or prevent the flow of thermal energy between conductive materials.

Subsequently aluminum windows and doors separating the frame into two separate interior and exterior pieces joined with a less conductive material reduces temperature transfer. Thermal breaks are made of hardy, rigid, low thermal conductive polyamide or polyurethane which is mechanically locked in aluminum window framing. Moreover thermal breaks can have the added benefit of reducing sound transmittance by dampening vibration.