This is your gateway to the laws, existing rules, rules in development, and policies for L&I’s program regulating manufactured and mobile homes, food trucks, and other mobile or modular structures. Here you can learn about:
- Applicable laws and rules.
- New rules being developed.
- How to get involved with the rulemaking process.
- New policies the program develops.
If you have a question about a rule, law or policy, email us at FAS1@Lni.wa.gov.
Laws & Rules
The state Legislature enacts laws regulating manufactured and mobile homes, food trucks, and other mobile or modular structures.
These laws are in chapters 43.22 and 43.22A of the Revised Code of Washington (RCW).
Agencies adopt rules to implement laws. Rules implementing the laws in chapter 43.22 and 43.22(a) are codified in the Washington Administrative Code (WAC) at Title 296-Chapter 49A, and 150C, 150F, 150I, 150M, 150P, 150R, 150T, and 150V.
The RCW and WAC are maintained and updated by the State Office of the Code Reviser.
If you receive an error message when referencing a link to a specific section of a WAC or RCW, try your search at the Washington State Legislative Search page.
For more information
- Overview of the L&I rulemaking process.
- A glossary of terms can help in understanding the rulemaking/code adoption process.
Laws
Revised Code of Washington (RCW)
- RCW 43.22 - Department of Labor & Industries.
- RCW 43.22A – Mobile and Manufactured Home Installation.
Code of federal regulations
Washington Administrative Code (WAC)
- Commercial Coaches –WAC 296-150C.
- Factory-Built Housing and Commercial Structures – WAC 296-150F.
- Manufactured Homes –WAC 296-150M.
- Manufactured Home Installer Certification –WAC 296-150I.
- Recreational Park Trailers –WAC 296-150P.
- Recreational Vehicles –WAC 296-150R.
- Factory Built Temporary Worker Housing Structures –WAC 296-150T.
- Concession Units and Medical Units – WAC 296-150V.
- Temporary Worker Housing Construction Standard – WAC 246-359.
Contact Us
FAS1@Lni.wa.gov
1-800-705-1411 Option 3
Mailing Address
Washington State Department of Labor & Industries
PO Box 44430
Olympia WA 98504-4430
Location
7273 Linderson Way SW
Tumwater WA 98501
When L&I officially announces a rule, it does so under law through permanent rulemaking, expedited rulemaking or emergency rulemaking changes to the Washington Administrative Code (WAC). Learn more about the rulemaking process and common rulemaking terms.
2025 rulemaking
L&I has adopted 6.51% fee increase for services from the Contractor Registration, Electrical, Elevator, Factory Assembled Structures (FAS), and Plumber programs.
The agency filed a CR-103 Rulemaking Order on May 5. The amount of the increase is the fiscal growth factor for fiscal year 2027. The increase represents the average personal income growth over the past decade.
This rulemaking also adopts housekeeping changes to the electrical rules to correct a mathematical error from a previous fee increase rulemaking.
The fee increase affects the following Washington Administrative Codes (WACs):
WAC 296-46B-906, Inspection Fees;
WAC 296-46B-909, Electrical/telecommunications contractor's license, administrator certificate and examination, master electrician certificate and examination, electrician certificate and examination, copy, and miscellaneous fees;
WAC 296-46B-911, Electrical testing laboratory and engineer accreditation fees;
WAC 296-96-00922, Licensing fees;
WAC 296-96-01085, Permit and inspection fees;
WAC 296-150C-3000, Commercial coach fees;
WAC 296-150F-3000, Factory-built housing and commercial structure fees;
WAC 296-150I-3000, Penalties, fees, and refunds;
WAC 296-150M-3000, Manufactured/mobile home fees;
WAC 296-150P-3000, Recreational park trailer fees;
WAC 296-150R-3000, Recreational vehicle fees;
WAC 296-150T-3000, Factory-built temporary worker housing fees;
WAC 296-150V-3000, Conversion vendor units and medical units – Fees;
WAC 296-200A-900, What fees does the department charge contractors for issuance, renewal, reregistration, and reinstatement of certificates of registration?; and
WAC 296-400A-045, What fees does the department charge for issuance, renewal, relicensing, and reinstatement of a plumbing contractor license and plumbing certificates?
The adopted fee increases take effect July 1.
Rulemaking documents
Notice of Intent (12/02/2025)
Proposed Rule Language (02/03/2026)
Final Adoption (05/05/2026)
For more information
- All FAS Program rulemaking.
- Overview of the L&I rulemaking process.
- A glossary of terms can help in understanding the rulemaking/code adoption process.
Contact us
FAS1@lni.wa.gov
1-800-705-1411 Option 3
Mailing Address
Washington State Department of Labor & Industries
PO Box 44430
Olympia, WA 98504-4430
Location
7273 Linderson Way SW
Tumwater WA 98501