For two-family dwellings, what is the minimum separation required between dwelling units?

In the context of two-family dwellings, the required minimum separation between dwelling units is typically a 1-hour fire-resistance rating. This requirement is rooted in the need to provide adequate protection against fire spread between living spaces, ensuring that occupants have sufficient time to evacuate and that adjacent units are safeguarded from potential hazards.

The 1-hour separation is established in the building codes, which aim to enhance safety in residential structures by minimizing risks associated with fire. This level of separation is generally achieved through the use of fire-rated walls or assemblies that meet the standard criteria outlined in the codes.

While there are provisions for reduced separation times in certain situations, such as when the structure is equipped with a fire suppression system, the default standard remains a 1-hour separation. This aligns with the codes designed to maintain occupant safety and property protection.

The options that suggest lesser separations or no separation at all do not reflect the minimum standards set forth to mitigate fire risks adequately. Therefore, the selection of a 1-hour separation accurately embodies the intent of the codes regarding residential fire safety.