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Flush Toilets Required?

sjh71nh

REGISTERED
Joined
Jul 8, 2025
Messages
3
Location
CA
Hi, the agency I work for is tearing down an existing building (structural failure) and rebuilding in the same location. It is on a well and the local soil cannot support a leach field. This is a rental property that although on a paved road is quite remote. I have been told that flushing toilets are required by the IPC but as I am doing a code review I cannot find where it says that it must be a flushing toilet and cannot be anything else. Is there a section that calls out flushing toilets only for rental cabin?
 
Maybe CPC 411.2? It says that "all water closets" shall have a certain flush volume, implying that the toilet needs to be a flushing type.

411.2 Water Consumption
The effective flush volume of all water closets shall not exceed 1.28 gallons (4.8 L) per flush when tested in accordance with ASME A112.19.2/CSA B45.1.

Edit: Oh, sorry, saw "CA" as your location and immediately assumed CPC / UPC. My bad... In IPC, I believe the section you're looking for is 425 or 604.4.
 
Thank you for that information. I am looking for the exception to flushing toilet. Currently there are outdoor vault toilets there and the goal would be to replace/reuse the existing toilets instead of installing new flush toilets.
 
Check with the local AHJ or Health Department to see if a composting toilet would be allowed.

Also you can search hear to see another thread and comments: Composting toilet
 

The IPC is silent on this subject. The IPSDC prohibits them. Your state health department may have requirements. You could have it go to a holding tank and have it pumped on a regular basis.

2024 International Private Sewage Disposal Code (IPSDC)​

PRIVY.
A structure, not connected to a plumbing system, that is used by persons for the deposition of human body waste.

302.2​

Privies shall be prohibited. Cesspools shall be prohibited, except where approved by the code official. Where approved, cesspools shall be designed and installed in accordance with Chapter 10.

You mentioned this would be a rental cabin. The IRC 2024 edition has this appendix section

Codes / I-Codes /
2024 International Residential Code (IRC)

Appendix CG Nonsewered Sanitation Systems​






2024 International Residential Code (IRC)​



The provisions contained in this appendix are not mandatory unless specifically referenced in the adopting ordinance.
User notes:


About this appendix: This appendix addresses the considerations that need to be taken into account by building officials regarding the placement and installation of nonsewered santiation systems in buildings. This appendix would permit the installation of a of these systems and provide an exception to the general requirement in the International Plumbing Code and this code that sanitation devices be connected to the building drainage system.

CG101​

INSIGHTS (3)

CG101.1​

The provisions of this chapter shall apply to the installation of nonsewered sanitation systems.
INSIGHTS (2)

CG101.2​

Nonsewered sanitation systems shall comply with ANSI/CAN/IAPMO/ISO CG106.1.
 

The IPC is silent on this subject. The IPSDC prohibits them. Your state health department may have requirements. You could have it go to a holding tank and have it pumped on a regular basis.

2024 International Private Sewage Disposal Code (IPSDC)​

PRIVY.
A structure, not connected to a plumbing system, that is used by persons for the deposition of human body waste.

302.2​

Privies shall be prohibited. Cesspools shall be prohibited, except where approved by the code official. Where approved, cesspools shall be designed and installed in accordance with Chapter 10.

You mentioned this would be a rental cabin. The IRC 2024 edition has this appendix section

Codes / I-Codes /
2024 International Residential Code (IRC)

Appendix CG Nonsewered Sanitation Systems​






2024 International Residential Code (IRC)​



The provisions contained in this appendix are not mandatory unless specifically referenced in the adopting ordinance.
User notes:


About this appendix: This appendix addresses the considerations that need to be taken into account by building officials regarding the placement and installation of nonsewered santiation systems in buildings. This appendix would permit the installation of a of these systems and provide an exception to the general requirement in the International Plumbing Code and this code that sanitation devices be connected to the building drainage system.

CG101​

INSIGHTS (3)

CG101.1​

The provisions of this chapter shall apply to the installation of nonsewered sanitation systems.
INSIGHTS (2)

CG101.2​

Nonsewered sanitation systems shall comply with ANSI/CAN/IAPMO/ISO CG106.1.
Excellent, thanks
 


 
Maybe CPC 411.2? It says that "all water closets" shall have a certain flush volume, implying that the toilet needs to be a flushing type.

411.2 Water Consumption
The effective flush volume of all water closets shall not exceed 1.28 gallons (4.8 L) per flush when tested in accordance with ASME A112.19.2/CSA B45.1.

Edit: Oh, sorry, saw "CA" as your location and immediately assumed CPC / UPC. My bad... In IPC, I believe the section you're looking for is 425 or 604.4.
Regarding California, the way 411.2 is worded, a no-water outhouse (zero gallons per flush) would comply with the requirement to not exceed 1.28 gallons per flush.
 
The IPC, is not the code in CA.


In CA ,
California Residential Building Code 2022

R306.1 Toilet Facilities
Every dwelling unit shall be provided with a water closet, lavatory, and a bathtub or shower.​
R306.2 Kitchen​
Each dwelling unit shall be provided with a kitchen area and every kitchen area shall be provided with a sink​
R306.3 Sewage Disposal​
Plumbing fixtures shall be connected to a sanitary sewer or to an approved private sewage disposal system.​
R306.4 Water Supply to Fixtures​
Plumbing fixtures shall be connected to an approved water supply.​
Kitchen sinks, lavatories, bathtubs, showers, bidets, laundry tubs and washing machine outlets shall be provided with hot and cold water.​

CPC 713.0 Sewer Required.
713.1 Where Required. A building in which plumbing fixtures are installed and premises having drainage piping thereon shall have a connection to a public or private sewer, except as provided in Section 713.2, and Section 713.4.​
713.2 Private Sewage Disposal System. Where no public sewer intended to serve a lot or premises is available in a thoroughfare or right of way abutting such lot or premises, drainage piping from a building or works shall be connected to an approved private sewage disposal system.​
713.3 Public Sewer. Within the limits prescribed by Section​
713.4 hereof, the rearrangement or subdivision into smaller parcels of a lot that abuts and is served by a public sewer shall not be deemed cause to permit the construction of a private sewage disposal system, and plumbing or drainage systems on a smaller parcel or parcels shall connect to the public sewer.​
713.4 Public Sewer Availability. The public sewer shall be permitted to be considered as not being available where such public sewer or a building or an exterior drainage facility connected thereto is located more than 200 feet from a proposed building or exterior drainage facility on a lot or premises that abut and is served by such public sewer.​
[HCD 1] For residential occupancies, the public sewer may be considered as not being available by the Authority Having Jurisdiction.​


STATE OF CALIFORNIA • UNINHABITABLE CONDITIONS
Civil Code Sections 1941.1 and 1941.3, Health and Safety Code Section 13113.7, and Health and Safety Code Sections 17920-17928
A dwelling may be considered uninhabitable (unlivable) if it substantially lacks any of the following:
"......​
• Plumbing facilities in good working order, including hot and cold running water furnished to appropriate fixtures, connected to a sewage disposal system.​
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.​
• A kitchen with a sink that cannot be made of an absorbent material such as wood. ....."​
 
Also in California Plumbing Code, this exception:

301.6 One- And Two-Family Dwellings

[HCD 1] The provisions contained in this code shall not apply to one and two-family dwelling private sewage disposal systems and minimum plumbing facilities when alternate facilities or installations have been approved by the local health authority, provided that such alternative facilities or installations provide substantially equivalent or greater protection to health and safety.


I know that pit toilets are allowed at remote camps, I wonder if there are similar regulations existing for remote single family residences:
Barclays California Code of Regulations
Title 17. Public Health
Division 1. State Department of Health Services (Refs & Annos)
Chapter 5. Sanitation (Environmental) (Refs & Annos)
Subchapter 6. Organized Camps
Article 2. Utilities

17 CCR § 30714
§ 30714. Toilets.
Toilets shall be provided at the ratio required in Table 4-4, Part 5, Title 24, California Code of Regulations. Pit or chemical toilets may only be used in remote areas where a plumbing system for water distribution is unavailable. Pit or chemical toilets shall be located so as not to endanger water supplies and shall be so constructed as to exclude flies and vermin.
Note: Authority cited: Sections 18897.2, 131050 and 131200, Health and Safety Code. Reference: Sections 18897.2, 131051 and 131052, Health and Safety Code.
History
1. Amendment filed 4-28-86; effective thirtieth day thereafter (Register 86, No. 18).
2. Amendment of section and Note filed 3-10-2008; operative 4-9-2008 (Register 2008, No. 11).
This database is current through 6/20/25 Register 2025, No. 25.
Cal. Admin. Code tit. 17, § 30714, 17 CA ADC § 30714
 
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