Where should the vapor barrier be installed when constructing a walk-in freezer box?

The vapor barrier should be installed outside on the warmest side. This is essential because the vapor barrier's primary purpose is to prevent moisture from the warmer side of the structure from penetrating the insulation and into the colder environment of the freezer. If moisture were allowed to enter, it could condense inside the insulation or within the freezer, leading to potential issues such as ice buildup, reduced efficiency, and compromise of the insulation's effectiveness.

Positioning the vapor barrier on the warm side helps ensure that any moisture present in the air is kept outside and does not infiltrate into the freezer space, thus maintaining the desired low temperatures and preventing energy loss. Ensuring the integrity of the vapor barrier's placement is a crucial aspect of constructing a walk-in freezer effectively.