(a) This subchapter does not apply to:
(1) a dwelling unit that is occupied by its owner, no part of which is leased to a tenant;
(2) a dwelling unit in a building five or more stories in height in which smoke alarms are required or regulated by local ordinance; or
(3) a nursing or convalescent home licensed by the Department of State Health Services and certified to meet the Life Safety Code under federal law and regulations.
(b) Notwithstanding this subchapter, a person licensed to install fire alarms or fire detection devices under Chapter 6002, Insurance Code, shall comply with that chapter when installing smoke alarms.