Whenever a new electrical box and hard wired smoke detector is required for compliance when selling, a licensed electrician is required to install the new electrical box and detector to current code. A new electrical box and new detector is required for any attached home when selling in the city of Los Angeles if it is missing one.
Here is the link to the city of Los Angeles code requirement, under Item #6.
Here is a quick primer on how exactly that is done from our electricians from the home and garden site The Spruce.
It takes experience and expertise not to destroy the existing drywall or lathe and plaster to install a new electrical box and new smoke detector.
The smoke detector is attached after new electrical box is installed in the wall or ceiling.
Call us with any questions you may have regarding this requirement and where it is required, or for the cost of our electricians to install one or multiple new hard wired detectors at your home at 310-800-4418.