For information on necessary permits for modifying a mobilehome, manufactured home, or commercial modular, visit the Modifying a Mobilehome page.

Please see Information Bulletin 2022-11: HCD Permit Requirements — Alterations or Conversions (PDF) for information on manufactured home/mobilehome alteration guidelines. The guidelines provide information on HCD’s permitting process, assist in determining what constitutes an alteration to a manufactured home/mobilehome, and assist in identifying when a form HCD MH 415 (PDF) is or is not required to be submitted to the Department.

HCD MH 415 - Manufactured Housing Permit Application (PDF)

Applications for some types of mobilehome and manufactured home alteration permits can be completed using Codes and Standards Online Services (C&S OS). Please login or create an account.

Form HCD MH 415 can be submitted to the Department by mail to the appropriate HCD Area Office or via email to:

• Northern Area Office at NAOstaff@hcd.ca.gov
• Southern Area Office at SAOstaff@hcd.ca.gov

Exception: HCD does not accept large format plans via email. These plans must be submitted by mail or in person.

When submitted to HCD, the completed application must be accompanied by the appropriate fees. Payment must be in the form of a check or money order payable to the Department of Housing and Community Development. Payments can also be submitted through the Department’s online fee-payment system. Please note: you must have a DTN and a zip code to make a payment online. This information can be obtained by contacting the appropriate Area Office at (800) 952-8356 or NAOstaff@hcd.ca.gov or SAOstaff@hcd.ca.gov.

The California Department of Housing and Community Development (HCD) provides a guideline for construction permit applicants to explain procedures and application requirements. The basic procedures and associated fees include:

• Obtain any necessary local agency approvals and complete all necessary plans, calculations, engineering, etc. required for processing your application.
• Consider contacting the appropriate Area Office for additional guidance regarding your application, plans and pertinent documents (project package).
• During the plan check staff will use the Mobilehome and Special Occupancy Park Construction Plan Review Booklet (PDF) as a worksheet to indicate if your project package is complete and ready to be submitted.
• Fees for preliminary plan check meetings are $196 per hour with a one-hour minimum.
• Include a copy of your worker's compensation insurance coverage.
• Submit your application and three (3) sets of plans with calculations and specifications to HCD's plan check section.
• Once the submittal is received in the plan check section, the plan will require four (4) to six (6) weeks for review.
• If the package is approved, you will receive your permit and job copy of the plans and documents by mail unless otherwise specified in advance.
• If the package is not approved, you will be contacted by mail and told whom you should contact. The approval process will be suspended until a satisfactory response is received.

Factory-built housing is inspected at the factory prior to application of the insignia.  Installation of factory-built housing or building components is subject to inspection by the local building department.