How long do I need to wait for Health Department approval?
You will need to check with LA County Health Department. It is recommended that you submit plans to the health Department as soon as you can. It may take few months to obtain your approval.
A single family zone only allows one house. You will need to obtain a variance from the Department of the City Planning for any additional dwelling unit on your property.
You can obtain one combined permit for the addition which covers the electrical, plumbing, HVAC, etc. work. However, a separate Sprinkler permit is required if the house needs to be sprinklered throughout due to the addition and remodeling.