Factory-Built Structures

Think of L&I as Washington's "building department" for all factory-built structures in the state.

Permits, Inspections & Fees
Find out how to get a permit to alter your factory-built structure and get it inspected afterwards. Includes technical definitions and pictures of various types of factory-built structures.

Installation Requirements
Find out when a certified manufactured/mobile home installer is required.

Installer Training & Certification
Washington law requires a certified manufactured home installer to be on site to supervise all phases of manufactured home installation work. Find out how to become a certified manufactured home installer. Get a list of certified mobile/ manufactured home installers.

What if you have problems?
Find out how to lodge a complaint against an alteration contractor or mobile home manufacturer.

Forms & Publications
Find forms and publications regarding factory-assembled structures.