(1) Adjacent structures shall be,
(a) separated by a distance equal to at least the square root of the sum of the squares of their individual deflections calculated in Sentence 4.1.8.13. (2), or
(b) connected to each other.
(2) The method of connection required in Sentence (1) shall take into account the mass, stiffness, strength, ductility and anticipated motion of the connected buildings and the character of the connection.
(3) Rigidly connected buildings shall be assumed to have the lowest RdRo value of the buildings connected.
(4) Buildings with non-rigid or energy-dissipating connections require special studies.