Title 24 Compliance

Title 24 refers to the California Building Standards Code, specifically Part 6, the Energy Code, which sets mandatory energy efficiency standards across the state—including for shipping-container-based structures. Within San Diego, these standards apply even to modular or container-based homes and must be addressed in permit submissions when the container is used as habitable space.


What the City of San Diego Requires: Information Bulletin 149

The City’s Information Bulletin 149 (March 2024) details the permitting and submittal requirements for using cargo containers as buildings. Here are the highlights:

Permit Requirements:

  • A building permit is required for any container installation—unless used temporarily for events, stage sets, or similar uses San Diego Government.
  • Separate permits are mandatory for electrical, plumbing, or mechanical systems when utilities are involved, regardless of the project being short-term or permanent.

Submittal Package Must Include:

  • Title 24 Energy calculations, if the container serves as habitable space.
  • Supporting documents: site and foundation plans, floor plans, elevations, landscaping, geotechnical reports (if needed), and hazard/material-related forms.
  • The title sheet must clearly state if HCD-approved factory-built containers are used, specifying: “Cargo containers … are approved by the California Department of Housing and Community Development (HCD).”


Using HCD-Approved Containers

Containers certified under California’s Factory-Built Housing Program (HCD) are accepted by the City once cleared through HCD procedures. The plan set must explicitly mention their HCD approval to streamline review.


Energy Code Essentials for San Diego (Title 24, Part 6)

San Diego falls under Climate Zone 8 for energy compliance. All habitable container structures must comply with:

  • Mandatory energy requirements (e.g., insulation, envelope tightness, ventilation, HVAC efficiency, lighting, hot water systems).
  • Performance or prescriptive compliance pathways tailored to this climate zone, using approved software and CF-1R (and other energy compliance) forms.

Recent statewide updates (e.g., 2025 rules) mandate all-electric baselines, battery storage, higher-efficiency HVAC, and advanced lighting controls—depending on project scale—but these mostly apply to new residential or larger commercial developments. Container homes may still benefit from considering these trends for future resilience.


County vs. City: San Diego County Exemptions

In unincorporated San Diego County, small, non-habitable container structures (≤ 120 sq ft) used as sheds or playhouses can be exempt from permits if they include no utilities and comply with zoning rules. However, once you add plumbing, electrical, or classify the structure as livable, a full permitting process, including Title 24 compliance, will be required.


Summary Checklist

1. Zoning Review

Confirm whether your property is under City jurisdictions or County. Check zoning designations, setback rules, and permits needed.

2. Determine Use

If the container is habitable—your project triggers Title 24 and full building code review.

3. Use HCD-Certified Containers?

If yes, state it clearly on title sheet for expedited approval. If no, ensure plans demonstrate full CBC compliance.

4. Prepare Submittal

Include energy compliance (Title 24 calculations/CF-1R forms), architectural and structural plans, utility diagrams, geotech (if needed), hazard forms, and other city-required documentation.

5. Compliance Approach

Adopt either prescriptive or performance approach per Title 24 Part 6; use state tools like Forms Ace, Reference Ace from Energy Code Ace platform.

6. Apply for Permits

Submit electronically through the City’s portal, paying attention to needed separate utility permits.

7. Inspections & Certifications

Plan for required inspections (structural, energy, plumbing, electrical) per CALGreen/HERS requirements and local code.


Final Thoughts

  • Title 24 applies fully to container homes in San Diego when they are occupiable.
  • City of San Diego's Bulletin 149 is your authoritative guide—your permit package must include Title 24 energy documentation along with traditional architectural and engineering plans.
  • HCD-certified containers can simplify the process—but only if clearly identified.
  • Always coordinate early with local building officials or a compliance specialist to avoid delays.
Contact Us