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The provisions given in Section 9.5.2.8 of ASCE 7 shall be used.

Exception: Structures designed using the simplified analysis procedure in Section 1617.5 shall meet the provisions in Section 1617.3.1.
1617.3.1 Deflection and Drift Limits (For Use in the Simplified Analysis Procedure of Section 1617.5)
The design story drift Δ, as determined in Section 1617.5.4, shall not exceed the allowable story drift Δa, as obtained from Table 1617.3.1 for any story. All portions of the building shall be designed to act as an integral unit in resisting seismic forces unless separated structurally by a distance sufficient to avoid damaging contact under total deflection as determined in Section 1617.5.4. Buildings shall not exceed the limitations of Section 1616.6.1.

TABLE 1617.3.1
ALLOWABLE STORY DRIFT, Δaa
BUILDING SEISMIC USE GROUP
I II III
Buildings, other than masonry shear wall or masonry wall frame buildings, four stories or less in height with interior walls, partitions, ceilings and exterior wall systems that have been designed to accommodate the story drifts 0.025 h sxb 0.020 h sx
0.015 h sx
Masonry cantilever shear wall buildingsc 0.010 h sx 0.010 h sx 0.010 h sx
Other masonry shear wall buildings 0.007 h sx 0.007 h sx 0.007 h sx
Masonry wall frame buildings 0.013 h sx 0.013 h sx 0.010 h sx
All other buildings 0.020 h sx 0.015 h sx 0.010 h sx
For SI: 1 inch = 25.4 mm.
  1. There shall be no drift limit for single-story buildings with interior walls, partitions, ceilings and exterior wall systems that have been designed to accommodate the story drifts.
  2. h sx is the story height below Level x.
  3. Buildings in which the basic structural system consists of masonry shear walls designed as vertical elements cantilevered from their base or foundation support which are so constructed that moment transfer between shear walls (coupling) is negligible.
1617.3.2 Structural Separations
All structures shall be separated from adjacent structures. When a structure adjoins a property line not common to a public way (typically side or rear lot lines), that structure shall also be set back from the property line by at least 1 inch (25 mm) for each 50 feet (15 240) of height. For structures in Seismic Design Category D, refer to Section 1620.4.5 for additional requirements.

Exception: Smaller separations or property line setbacks shall be permitted when justified by rational analysis based on maximum expected ground motions.

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