(1) Wherever “resist” or “sustain” occurs in Chapter, it shall mean resist or sustain, as the case may be, at the stresses permitted in this Chapter.

(2) Wherever “wall” or “walls” occurs, it shall not mean a veneered wall or walls, unless stated to the contrary.

(3) Wherever the thickness of a wall is mentioned, it shall mean the actual thickness, unless the effective thickness is stipulated.