Attic fireblocking or draft stopping is not required at the partition line in a Group R-2 building if it does not exceed how many stories above grade plane?

In the context of Group R-2 buildings, which typically include residential occupancies such as apartment complexes, the requirement for attic fireblocking or draft stopping enhances safety by preventing the spread of fire and smoke through concealed spaces. The code provides guidelines on when these requirements apply based on the number of stories above the grade plane.

For a Group R-2 building that does not exceed four stories, fireblocking or draft stopping at the partition line is not mandated. This provision is intended to balance safety with practicality, recognizing that at four stories or fewer, the risk and potential impact of fire spread can be managed through alternative means or due to the building's overall design and construction standards.

In essence, if a Group R-2 building is four stories or fewer, the code permits some flexibility regarding fireblocking requirements, allowing for a more straightforward construction process without compromising safety. Higher story counts would necessitate stricter fire protection measures to mitigate fire risks effectively.