Ceiling temperature () is a measure of the tendency of a polymer to revert to its constituent monomers. When a polymer is at its ceiling temperature, the rate of polymerization and depolymerization of the polymer are equal.  Generally, the ceiling temperature of a given polymer is correlated to the steric hindrance of the polymer’s monomers.  Polymers with high ceiling temperatures are often commercially useful. Polymers with low ceiling temperatures are more readily depolymerizable.