# Condition for Closed Extension Space to be T5 Space

## Theorem

Let $T = \struct {S, \tau}$ be a topological space.

Let $T^*_p = \struct {S^*_p, \tau^*_p}$ be the closed extension space of $T$.

Then $T^*_p$ is a $T_5$ space if and only if $T$ is a $T_5$ space vacuously, and $T^*_p$ in this case is also a $T_5$ space vacuously.