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.
2022 rulemaking
Plan review by licensed professionals
L&I adopted changes that modify rules for design plan reviews by licensed professional engineers, architects, and firms for commercial coach trailers, factory-built housing and commercial structures, recreational park trailers, recreational vehicles, and conversion vendor units (food trucks and trailers).
L&I filed emergency rules to address a backlog of design plans in the Factory Assembled Structures Program (FAS) (see above). This rulemaking adopts permanent rules.
The changes affect rules under:
- Chapter 296-150C WAC, Commercial Coaches.
- Chapter 296-150F WAC, Factory-built housing and commercial structures.
- Chapter 296-150P WAC, Recreational park trailers.
- Chapter 296-150R WAC, Recreational vehicles.
- Chapter 296-150V WAC, Conversion vendor units and medical units.
The new rules took effect on April 11, 2023.
Rulemaking Documents
Notice of Intent 8/16/22
- CR-101 Pre-proposal.
- Draft Rule Language–Version 1 – Full Version.
- Draft Rule Language–Version 1 – Short Version.
Proposed Rule Language 2/28/23
- CR-102 Proposed Rulemaking.
- CR-102 Proposed Rule Language.
- Preliminary Cost Benefit Analysis.
- Public Hearing Information Packet.
Final Adoption 4/11/2023
- CR-103 Adoption
- CR-103 Adoption Language
- Concise Explanatory Statement (CES)
- Final Cost Benefit Analysis
Rulemaking for new legislation
During the 2019 legislative session, the state Legislature enacted laws affecting factory assembled structures. The changes included:
- Requirements for energy efficiency.
- Delegation of inspection duties.
- Tiny houses.
These changes require L&I to engage in rulemaking.
During the 2019 legislative session, L&I separately filed a preproposal statement of inquiry (called a CR-101) (WSR 19-06-069, filed March 5, 2019). The preproposal would have adopted rules allowing for inspection and approval of manufactured building panels prior to shipment to a construction site within the state. The preproposal would also have made updates, clarifications, and housekeeping changes.
Instead of conducting two separate rulemakings - one to address legislative changes and one to consider a new rule - L&I has determined it is a better use of agency resources to consolidate all of the required changes into one rulemaking.
As a matter of procedure, the agency has withdrawn the preproposal. The agency instead has filed a new preproposal to consider changes to WAC chapter 296-150F related to:
- Requirements for energy efficiency.
- Delegation of inspection duties.
- Tiny houses.
- Inspection and approval of manufactured building panels prior to shipment to a construction site within the state.
- Updates, clarifications, and housekeeping changes.
Rulemaking documents
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