http://www.dca.ca.gov/publications/landlordbook/problems.shtml#conditionsmakeuninhabitable
Conditions that make a rental unit legally uninhabitable
There are many kinds of defects that could make a rental unit unlivable. The implied warranty of habitability requires landlords to maintain their rental units in a condition fit for the "occupation of human beings "123 In addition, the rental unit must “substantially comply” with building and housing code standards that materially affect tenants’ health and safety.124
A rental unit may be considered uninhabitable (unlivable) if it contains a lead hazard that endangers the occupants or the public, or is a substandard building because, for example, a structural hazard, inadequate sanitation, or a nuisance endangers the health, life, safety, property, or welfare of the occupants or the public.125
A dwelling also may be considered uninhabitable (unlivable) if it substantially lacks any of the following:126
* Effective waterproofing and weather protection of roof and exterior walls, including unbroken windows and doors.
*** Plumbing facilities in good working order, including hot and cold running water, connected to a sewage disposal system**
* Gas facilities in good working order.
* Heating facilities in good working order.
* An electric system, including lighting, wiring, and equipment, in good working order.
* Clean and sanitary buildings, grounds, and appurtenances (for example, a garden or a detached garage), free from debris, filth, rubbish, garbage, rodents, and vermin.
* Adequate trash receptacles in good repair.
* Floors, stairways, and railings in good repair.
In addition to these requirements, each rental unit must have all of the following:
*** A working toilet, wash basin, and bathtub or shower. The toilet and bathtub or shower must be in a room which is ventilated and allows privacy.**
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