(1) The provisions of these rules shall apply to:

(a) All dwelling units occupied by persons other than the owner after December 31, 1981;

(b) All dwelling units built or manufactured in this state after December 31, 1980; and

(c) All dwelling units sold on or after July 1, 2019.

(2) Notwithstanding the provisions of chapter 19.27 RCW, RCW 43.22.340 through 43.22.434 and 43.22.450 through 43.22.490, the provisions of these rules shall also apply to all buildings or structures, mobile homes and factory built housing used as dwelling units.