A thermal seal, also known as a “double-pane” or “insulated” window, is a window that has two panes of glass with a sealed air space between them. This air space is filled with an insulating gas, such as argon, which helps to reduce heat transfer and improve energy efficiency. When a thermal seal is broken, it means that the seal between the two panes of glass has failed and the insulating gas has escaped. Here are some potential consequences of a broken thermal seal: 1.Reduced energy efficiency: A broken thermal seal can significantly reduce the energy efficiency of a window. Without the insulating gas, heat can transfer more easily between the inside and outside of the home, leading to higher heating and cooling costs. 2.Condensation: When a thermal seal is broken, moisture can enter the space between the two panes of glass. This can lead to condensation forming on the inside of the window, which can obscure the view and potentially cause damage to the window frame or sill. 3. Mold growth: If condensation forms on the inside of the window, it can create a moist environment that is conducive to mold growth. This can be a health hazard and may require professional remediation. 4. Fogging: A broken thermal seal can cause the window to appear foggy or cloudy. This can be unsightly and can make it difficult to see through the window. 5. Damage to window frame: If moisture gets into the space between the panes of glass, it can cause damage to the window frame or sill. This can lead to further repairs or even window replacement.