The Ontario Building Code | Structural Separation
220.127.116.11. Structural Separation
(1) Adjacent structures shall either be separated by the square root of the sum of the squares of their individual deflections calculated in Sentence 18.104.22.168.(2), or shall be 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.