Cal. Civ. Code § 38-12-505

(1) A
residential premises is deemed uninhabitable if:

(a) 
There is mold that is associated with dampness, or there is any other condition
causing the residential premises to be damp, which condition, if not remedied,
would materially interfere with the health or safety of the tenant, excluding
the presence of mold that is minor and found on surfaces that can accumulate
moisture as part of their proper functioning and intended use;

(b) It
substantially lacks any of the following characteristics:

(I) 
Functioning appliances that conformed to applicable law at the time of
installation and that are maintained in good working order;

(II) 
Waterproofing and weather protection of roof and exterior walls maintained in
good working order, including unbroken windows and doors;

(III) 
Plumbing or gas facilities that conformed to applicable law in effect at the
time of installation and that are maintained in good working order;

(IV) 
Running water at all times and hot water in an amount necessary for the tenant
to perform all ordinary activities related to maintaining cleanliness and
health, furnished to appropriate fixtures and connected to a sewage disposal
system approved under applicable law;

(V) 
Functioning heating facilities that conformed to applicable law at the time of
installation and that are maintained in good working order;

(VI) 
Electrical lighting, with wiring and electrical equipment that conformed to
applicable law at the time of installation, maintained in good working order;

(VII) 
Common areas and areas under the control of the landlord that are kept
reasonably clean, sanitary, and free from all accumulations of debris, filth,
rubbish, and garbage and that have appropriate extermination in response to the
infestation of rodents, vermin, pests, or insects;

(VIII) 
Appropriate extermination in response to the infestation of rodents, vermin,
pests, or insects throughout a residential premises, including compliance with
all requirements under part 10 of this article 12;

(IX) An
adequate number of appropriate exterior receptacles for garbage, waste, and
rubbish, in good repair and scheduled to be serviced and emptied at sufficient
intervals to ensure containment and proper disposal of all trash, waste, and
rubbish;

(X) 
Floors, stairways, elevators, and railings maintained in good repair;

(XI) 
Locks on all exterior doors and locks or security devices on windows designed
to be opened that are maintained in good working order;

(XII) 
Compliance with all applicable building, housing, and health codes, the
violation of which would constitute a condition that materially interferes with
the life, health, or safety of the tenant;

(XIII) 
Compliance with applicable standards from the American National Standards
Institute, or its successor organization, and all applicable provisions of
building, fire, health, and housing codes for the remediation and cleanup of a
residential premises following an environmental public health event;

(XIV) 
Remediation in compliance with article 18.5 of title 25 if the residential
premises was used as an illegal drug laboratory, as defined in section
25-18.5-101 (8), involving methamphetamine.

(XV) 
Compliance with all requirements in section 38-12-803; or

(XVI) 
Compliance with all requirements related to cooling devices established in
subsection (7) of this section; or

(c) It
is otherwise unfit for human habitation.

(2) A
deficiency in the common area shall not render a residential premises
uninhabitable as set forth in subsection (1) of this section, unless it
materially affects the tenant's use of the tenant's dwelling unit.

(3) (a) 
Before a landlord leases a residential premises to a tenant, the landlord must
ensure that the residential premises is fit for human habitation in accordance
with section 38-12-503 (1) and that the residential premises is not in a
condition described in subsection (1) of this section.

(b) A
landlord that leases a residential premises that is not in compliance with this
section breaches the warranty of habitability pursuant to section 38-12-503
(1), and the tenant may pursue any remedy under section 38-12-507.

(c) On
and after January 1, 2025, every rental agreement between a landlord and tenant
must include a statement in at least twelve-point, bold-faced type that states
that every tenant is entitled to safe and healthy housing under Colorado's
warranty of habitability and that a landlord is prohibited by law from
retaliating against a tenant in any manner for reporting unsafe conditions in
the tenant's residential premises, requesting repairs, or seeking to enjoy the
tenant's right to safe and healthy housing.

(d) On
and after January 1, 2025, every rental agreement between a landlord and tenant
must include a statement in English and Spanish and in at least twelve-point,
bold-faced type that states an address where a tenant can mail or personally
deliver written notice of an uninhabitable condition and an email address or
accessible online tenant portal or platform where a tenant can deliver written
notice of an uninhabitable condition.

(e) If
a landlord provides a tenant with an online tenant portal or platform, the
landlord must post in a conspicuous place in the online tenant portal or
platform a statement in English and Spanish that states an address where a
tenant can mail or personally deliver written notice of an uninhabitable
condition and an email address or accessible online portal or platform where a
tenant can deliver written notice of an uninhabitable condition.

(4) 
There is a rebuttable presumption that the following conditions at a
residential premises materially interfere with a tenant's life, health, or
safety pursuant to section 38-12-503 (2)(a)(II):

(a) 
Lack of waterproofing and weather protection for the roof, exterior walls,
exterior doors, and exterior windows of a dwelling unit so that weather-related
elements can enter the dwelling unit;

(b) Any
hazardous condition of gas piping, gas facilities, gas appliances, or other gas
equipment;

(c) 
Inadequate running water or inadequate running hot water, except for temporary
disruptions in water service due to necessary maintenance, repair, or
construction that is being performed or temporary disruptions in water service
that a landlord could not reasonably prevent or control;

(d) 
Lack of functioning heating facilities and equipment fixtures that are
installed and operating in compliance with applicable law at the time of
installation and that are maintained in good working order from October through
April of each year;

(e) Any
hazardous condition of electrical wiring, electrical facilities, electrical
appliances, or other electrical equipment;

(f) 
Lack of electricity or disruptions of electricity that are caused by a
landlord's failure to maintain electrical wiring, electrical facilities,
electrical appliances, or electrical equipment;

(g) 
Lack of working locks or security devices on all exterior doors that allow
entry into a residential premises or a dwelling unit and all exterior windows
that are designed to be opened;

(h) 
Lack of working plumbing or sewage disposal or any condition that allows
sewage, water, moisture, or other contaminants to enter the residential
premises other than through properly working plumbing and sewage disposal
systems;

(i) An
infestation of rodents, vermin, pests, or insects;

(j) Any
inaccessible fire exits or egress in accordance with applicable building,
housing, fire, and health codes;

(k) Any
missing, damaged, improper, or misaligned chimney or venting on any fuel-fired
heating, ventilation, or cooling system; or

(l) An
inoperable elevator when the tenant has a disability that prevents the tenant
from being able to use the stairs to access the tenant's dwelling unit or the
tenant relies on an elevator to access the tenant's dwelling unit and there are
no other operable elevators that provide access to the tenant's unit.

(5) A
landlord may rebut the presumption in subsection (4) of this section by
demonstrating, through clear and convincing evidence, that a condition listed
in subsection (4) of this section does not materially interfere with a tenant's
life, health, or safety.

(6) 
Nothing in this section prevents a court or jury from finding that any
condition or combination of conditions described in this section materially
interferes with a tenant's life, health, or safety.

(7) (a) 
A landlord shall not prohibit or restrict a tenant from installing or using a
portable cooling device, including under any rental agreement or other
agreement between the landlord and the tenant; except that the landlord may
prohibit or restrict the installation or use of a portable cooling device if
the installation or use of the portable cooling device would:

(I) 
Violate any building codes, state law, or federal law;

(II) 
Violate the portable cooling device manufacturer's written safety guidelines
for installing or using the device;

(III) 
Damage the premises or render the premises uninhabitable; or

(IV) 
Require more amperage to power the portable cooling device than can be
accommodated by the residential premises', dwelling unit's, or circuit's
electrical capacity.

(b) A
landlord that restricts the installation or use of portable cooling devices at
a residential premises with multiple dwelling units under subsection (7)(a)(IV)
of this section shall prioritize a tenant who requests the installation or
usage of a portable cooling device to accommodate the tenant's disability over
other tenants' requests to install or use a portable cooling device.

(c) A
landlord that restricts the installation or use of a portable cooling device at
a residential premises under subsection (7)(a) of this section shall:

(I) 
Disclose any restrictions on the installation or use of portable cooling
devices to a tenant or prospective tenant in writing;

(II) 
Provide information about whether the landlord intends to operate one or more
common spaces at the residential premises that will be cooled by a portable
cooling device or permanent cooling device and available to the tenant during
an extreme heat event; and

(III) 
If the landlord does not intend to operate common spaces at the residential
premises that will be cooled by a portable cooling device or permanent cooling
device, provide information on community cooling spaces that are located near
the residential premises and accessible to the tenant during an extreme heat
event; except that a landlord is not required to provide information on
community cooling spaces if there are no known community cooling spaces within
ten miles of the residential premises.

(d) (I) 
As used in this subsection (7), unless the context otherwise requires,
"community cooling spaces" means public spaces that are available to
a tenant and that are located on or near the residential premises and that
maintain a temperature that is not higher than eighty degrees Fahrenheit.

(II) 
"Community cooling spaces" may include recreation centers, community
centers, and public libraries.

(e) 
Nothing in this subsection (7) modifies a landlord's obligation to permit
reasonable modifications and reasonable accommodations for individuals with a
disability under section 24-34-502.2.