(3) Multi-unit residence common areas; except that a landlord or common interest development may designate a portion of the outdoor area a smoking area. A designated smoking area:
(i) must be located at least twenty (20) feet from any operable window or door used by the public of an indoor area of a multi-unit residence where smoking is prohibited;
(ii) must not include, and must be at least twenty (20) feet from, outdoor areas primarily used by children including, but not limited to, areas improved or designated for play or swimming;
(iii) must be no more than twenty-five (25) percent of the total outdoor area of the premises for which it is designated;
(iv) must have a clearly marked perimeter;
(v) must be identified by conspicuous signs; and
(vi) must not overlap with any area in which smoking is otherwise prohibited by this chapter or other provisions of this Code, state law, or federal law.
(4) Individual units of multi-unit residences, if such units share at least one common floor or ceiling with another such unit.
A copy of the ordinance is available here.
So, unless you are in a single family residence in Belmont, you’ll need to get your butt outside, if you want to have a smoke.