Why Do Oven Doors Shatter and How to Prevent It?

Oven doors can shatter for a variety of reasons, and the causes are often a mix of material properties and small imperfections that are invisible to the eye. Most people assume that something dramatic must have happened for an oven door to break, but in reality, the explanation is usually more subtle. Understanding why this occurs can help homeowners prevent accidents and keep their appliances functioning safely.

The glass used in oven doors is not ordinary household glass. Manufacturers typically rely on two main types. One is tempered soda lime glass. It is strong and heat resistant, but it has a lower tolerance for sudden changes in temperature. The other is borosilicate glass, which is known for its durability and superior ability to withstand rapid shifts in heat. Although both types are engineered for high temperatures, neither is completely immune to stress. Whenever an oven heats up and cools down, the glass expands and contracts. Over time, these small movements can create internal pressure.