The purpose of this information bulletin is to explain permitting requirements for using cargo containers repurposed as buildings. Cargo Containers are also known as intermodal shipping containers. Cargo Containers shall comply with the California Building Code (CBC), Chapter 31, Section 3115.

I. Permit Requirements

All cargo containers, whether or not approved by the California Department of Housing and Community Development (HCD) as Factory Built Housing, shall comply with permitting requirements stated in this section, as well as applicable provisions of the California Building Standards Code and the Land Development Code. A Building Permit shall be obtained to install cargo containers on a site except for the following conditions: When used as a part of stage sets or other production proposed during a permitted special event.

1. A separate electrical, mechanical and plumbing permit is required when a cargo container is supplied with electricity, gas, water, or sewer utilities, regardless of whether installed on a temporary or permanent basis.
2. Historical Review

If a structure is 45 years old or older is located on a site where a cargo container is to be placed, the project is subject to a Potential Historical Resource Review. Please refer to Information Bulletin 580, “Potential Historical Resource Review.” If boundaries of adopted historical districts designate the site, or it is determined eligible for or listed in the California or National Registers, the project is subject to Designated Historical Resource Review. Please refer to Information Bulletin 581, “Designated Historical Resource Review.”

II. Submittal Requirements

All new permit applications are required to be submitted electronically. To apply for a permit and for information on the digital submittal process, refer to the Department’s website. For information on the submittal requirements, refer to the Project Submittal Manual.

1. Forms to Complete
   All cargo container plans must be submitted with the following forms:
   1. A Project Contacts Form (DS-345)
   2. Water Meter Data Card (if the container contains any plumbing fixtures-Form DS-16)
   3. Hazardous Material Reporting Form (Form DS-165)
   4. San Diego Regional Hazardous Material Questionnaire (Form HM-9171)
   5. Storm Water Requirements Applicability Check List (Form DS-560)
   6. Owner-Builder Verification if the owner is applying for the permit (Form DS-3042)
2. Drawings, Calculations and Reports
   A cargo container installation project must include the following drawings and calculations:
   1. Site Plan and Vicinity Map per Information Bulletin 122.
   2. Foundation plan and details.
   3. Floor plan showing all plumbing fixtures.
   4. Elevations with dimensions.
   5. Landscape Plan.
   6. Geotechnical Investigation Report where required per San Diego Municipal Code, Chapter 14, Article 5, Division 18.
   7. Title 24 Energy calculations (if used as habitable space).
   8. Additional requirements specified in CBC Sections 3115.2, 3115.3, 3115.8.4.
3. Information on Title Sheet
   The following information shall be provided in a table format on the first sheet of the plans:
   1. Scope of Work:  Briefly describe the scope of work of the project. For example, the scope of work includes the installation of one detached metal cargo container for use as a storage shed. If HCD-approved containers are proposed to be used, the scope of work on the title sheet of the constructions must clearly state, “Cargo Containers used for this project are approved by the HCD.”
   2. Sheet Index: List of all the sheets included in the plan package.
   3. Project Team: list name, address, and phone number of all design professionals.
   4. Legal description and Assessor Parcel number(s) for the property on which the development is proposed.
   5. Owner’s name(s) and address(es).
   6. Proposed use.
   7. Zoning designation and/or overlay zone designations (Coastal, Coastal Height Limit, Airport Influence Area, etc.).
   8. Any approved development permits (discretionary permits) for the project.
   9. Type of Construction: Cargo Containers are classified as Type V0B construction unless specified otherwise.
   10. Occupancy Classification (s) per the CBC.
   11. The Building Code Year edition used for the design of the project.
   12. The number of containers stacked (for example, single or double).
   13. The overall height of the container from the top of adjacent to the highest point of elevation.
   14. The gross floor area and floor area ratio (if applicable).
   15. Condition of soil (undisturbed, compact fill, or loose fill) when the proposed construction includes a new foundation system, with a reference to the project geotechnical investigation report.
   16. Landscape area square footage for water conservation purposes.
   17. Total area of disturbance. For more information, refer to Section 2 of the Land Development Manual, Volume 1, Chapter 1, Project Submittal Requirements.
4. Accessibility
   Cargo Containers utilized as privately funded covered multifamily dwellings or as public buildings, public accommodations, commercial buildings, or public housing are subject to the accessibility standards of the CBC, chapter 11A or Chapter 11B as applicable. Cargo containers utilized as a combination of privately funded and publicly funded multifamily dwellings shall comply with the most restrictive accessibility standards specified in CBC Chapters 11A and 11B.
5. Foundation System
   A permanent foundation system is required to support containers when containers are stacked (multi-level), containers are used for residential occupancy, or when containers are supplied with electrical, water, gas or sewer utilities, A foundation plan showing an engineered foundation system, including specifications, connection, and sectional details shall be provided. This foundation plan shall bear the approval stamp of a California registered civil or structural engineer or a California-licensed architect, signature and date.

   Exceptions: Single cargo containers may be placed on even grade (not sloping more than ¼ inch per foot) without a supporting foundation system, provided:

   1. Grade is level with suitable material for supporting such containers and
   2. Cargo container is not supplied with electric, water, gas, or sewer utilities.
6. Roof Assembly and Coverings
   Roof assembly and roof coverings shall be Class A and listed in accordance with ASTM E108 or UL 790. Specifications and details for the proposed roof assembly shall be shown on the roof plan.
7. Fire Sprinkler Systems
8. Containers used for residential occupancy are required to be equipped with an automatic sprinkler system unless exempted. For detailed information describing the procedures and requirements related to a fire sprinkler permit for single-family home, duplex, or townhome, see Information Bulletin 124, "Residential Fire Sprinklers."
9. Containers used for multi-dwelling units, transient lodging or non-residential occupancy may be required to be equipped with an automatic sprinkler system. For detailed information describing the procedures and requirements related to a fire sprinkler permit, see Information Bulletin 139, "Fire Sprinkler Systems."
10. Stamp and Signature of Licensed Professional on Plans
    Cargo containers specified on plans are not considered conventional construction. Their use must be specified by a California-licensed design professional.  Therefore, all sheets of construction plans and first sheet of structural calculations shall be stamped and signed by a California licensed architect or a registered Civil or Structural engineer.

    Exception: Sheets of plans approved and bearing the stamp of approval by tHCD.

III. Use of Containers Approved by California Department of Housing and Community Development (HCD)

In addition to the requirements stated in Sections I and II above, HCD-approved cargo containers reviewed and approved by the California Department of Housing and Community Development (HCD) are accepted by the City as approved for the stated occupancy and intended purpose. Projects using factory-built container-based units or structures must be certified through HCD’s Factory-Built Housing Program. Each HCD-approved cargo container shall bear a State of California insignia, which identifies the container as a container approved for the specified use and occupancy.  When HCD-approved cargo containers are used for the project:

1. The scope of work on the title sheet of construction plans must clearly state, “Cargo containers used for this project are approved by the California Department of Housing and Community Development (HCD).”

2. HCD-approved factory-built units shall comply with the requirements specified in Information Bulletin 241, Factory-Built Housing.

IV. Use of Containers Not Approved by California Department of Housing and Community Development (HCD)

In addition to the requirements stated in Section I and II above, containers not HCD-approved are also subject to the following. Cargo container conversions NOT approved by HCD shall comply with CBC, Chapter 31, Section 3115 and the following specific requirements:

1. Safety Standard Notes on Plans
   The following safety standard notes shall be added on the cover sheet or on the floor plan by the design architect of record. The sheet plan showing the following notes shall be stamped and signed by the California-licensed architect of record:
   1. Containers used in this project shall meet or exceed applicable industry safety standards for the intended use and purpose as proposed, be free of any chemical hazards, and be fit for human use and occupancy. 
   2. Cargo containers specified on the construction drawings and to be converted to building modules in the project shall be standard dry cargo containers and used for one-way transportation of dry goods only.
   3. Containers used in the project shall not have been used for transporting hazardous materials.
   4. Containers used in the project shall not have been painted with products containing lead.
   5. Containers will be visually inspected and verified by the design architect or structural design engineer of record or by a Licensed Marine Surveyor as undamaged and have had no previous repairs.
   6. A City-registered welding special inspector shall visually inspect and verify all weldments throughout each container to be in structurally sound condition in accordance with governing AWS Standards.
   7. The existing plywood floor sheathing, if to remain in place, shall be inspected and be free of any signs of damage, delamination, dry rot, or deterioration.
   8. All items requiring repairs due to damage or failure shall be reported to the structural design engineer of record for remedy.  All repair details and specifications shall be shown on plans for review and approval.
2. Evaluation and Structural Observation Report
   A written evaluation and structural observation report prepared by the design architect or structural design engineer of record shall be submitted to the building official addressing all of the issues stated in Section IV-A.
3. Structural Calculation
   Structural calculations shall be provided for the following conditions to justify for adequacy of the structural capacity of cargo containers:
   1. Cargo containers altered such as by the removal of any part of any part of the exterior walls, floors, or roof plane, the addition of doors, windows, or skylights.
   2. Multiple cargo containers connected together by welding or bolted connections.
   3. Cargo containers stacked.
4. Testing

1. The design strengths and permissible stresses for the material of the container shall be established by tests as provided for in Section 1707 of the CBC when such material properties cannot be identified by the manufacturer’s designation as to manufacture and mill test.
2. When construction of cargo containers are altered or modified, in situ load test shall be required in accordance with Section 1709 of the CBC. For additional information, refer to Technical Bulletin 17-6, "Testing and Inspections for Proof of Compliance."

5. Stacking
   Cargo containers may be stacked.  A complete and comprehensive structural calculation providing justification for vertical and lateral load demand for the entire system and connection details shall be submitted, giving consideration to all applicable loads prescribed per CBC. Such stacked cargo containers shall be supported on a foundation system.

V. Use of Single Level Cargo Containers Not Approved by HCD for Residential and Commercial Buildings

Containers that are not approved by HCD may be used as residential or commercial buildings provided that they comply with all of the following prescriptive requirements:

1. Containers shall be single-unit and not to exceed one level above grade plane. Stacking of containers is not allowed. Multi-level containers are not allowed.
2. Containers may be used for residential occupancy Group (R-1, R-2, or R-3) or non-residential occupancy Group (B, M. S, U).
3. Containers shall be located and supported on grade. Consideration shall be given to the separation of wood floor sheathing from top of grade due to deterioration by providing 18 inches minimum clearance of pressure-treated wood floor sheathing.
4. Containers must be detached and independent of any adjacent buildings or structures.  Multiple single-unit containers may be placed horizontally and connected together.
5. Containers shall be standard-sized, and their original manufactured physical dimensions (width, length, and height) shall not be altered.
6. Roof and walls of containers may be altered to add openings for skylights, windows, or doors provided the containers' structural vertical load and lateral load strength capacity are maintained and verified by the California registered civil/engineer (structural design engineer of record). Such openings must be framed with steel elements.  Details of framing around openings shall be shown on the plans. Structural engineering design calculations and testing are not required.
7. Containers shall comply with all other requirements stated in Sections I, II and IV in this bulletin.
8. Roof of containers shall not be occupied or used for any purpose.
1. Containers shall be positively anchored at each of their four corners to the support foundation.  Details of foundation and anchorage shall be provided on plans.
10. All sheets of plans and specifications shall be stamped and signed by the California-licensed architect or a registered civil/structural engineer of record.

VI. Fees

The following fees will be applied to Cargo Container projects:

1. Building Permit Fees. Refer to Information Bulletin 501, “Fee Schedule, Construction Permits-Structures."

2. Mechanical/Plumbing/Gas, Electrical Fees. Refer to Information Bulletin 103, “Fee Schedule for Mechanical, Electrical, Plumbing/Gas Permits."

3. Water and Sewer Fees.  Water and sewer capacity fees are due when the container contains plumbing fixtures and/or the property will be irrigated. For more information, refer to Information Bulletin 501, “Fee Schedule for Construction Permits-Structures”.

4. School Fees. Cargo containers are subject to school fees in accordance with Section 65995 of the California Government Code and as authorized under Section 17620 of the Education Code. Refer to Information Bulletin 146, "School Fees."