For a wall with a fire-resistance rating of 1 hour, what should its door assembly be rated?

For a wall with a fire-resistance rating of 1 hour, the appropriate door assembly fire rating is generally required to match or be less than that of the wall itself. In this case, if the wall is rated for 1 hour, the door assembly should typically have a fire-resistance rating of at least 45 minutes to provide adequate protection and maintain the fire integrity of the barrier.

This is essential for limiting the spread of fire and smoke, ensuring the safety of occupants by allowing safe egress during a fire event. A door assembly rated at 30 minutes may not offer sufficient protection to match the wall's fire-resistance rating, while a rating of 1 hour would be compliant, but for many applications, a 45-minute rating presents a more appropriate balance between safety requirements and practical application.

A 1.5-hour rating would exceed the wall's rating and is unnecessary for this scenario, as it does not align with code requirements and could lead to complications in construction and compliance. Thus, the 45-minute door assembly serves to provide adequate protection while remaining within practical compliance standards.