Find a certified mobile/ manufactured home installer here.

When is a certified manufactured/mobile home installer required?

Does a person have to be certified to work on their own home?

No. A homeowner may do work on their own residence. The homeowner may have friends or family help with the installation. However, if the homeowner pays anyone to do any part of the installation work, that person must be certified.
Are individuals and companies who receive pay to install manufactured homes required to obtain a special license or certification?

Yes. Revised code of Washington 43.22A requires certification of manufactured home installers.
Is installer certification required of a manufactured/mobile home park owner or dealer installing homes intended for sale or rental?

Yes.
Can more than one certified installer be involved in installing a mobile or manufactured home?

A certified installer is required to be on site at all times during each phase of installation. There may be different certified installers for each phase of installation. There is no requirement that the same certified installer supervise an installation from start to finish.

However, if two or more certified installers perform different aspects of the installation, one certification tag is required for each installer. For more information, see note below regarding tags.
What types of M/MH installation work require a certified installer?

Installation work requiring a certified manufactured home installer is:

Construction of the foundation system, including building forms for concrete.
Setup and assembly.
Installing the support piers.
Installing earthquake resistant bracing systems.
Connection to the foundation system and support piers.
Re-leveling of the home.
Installing skirting of any kind, decorative or load-bearing.
Connections to the on-site water and sewer systems for normal operation of the home.
Installing ground anchors.
Service work to the home that falls under the definition of manufactured home installation.

Installer certification is not required for licensed plumbers or electricians working within the scope of their license.

Expand/collapse What types of M/MH installation work do not require a certified installer?

Site preparation such as grading and excavation.
Sewer and water connections outside of the building site.
Pouring concrete into forms.
Painting and drywall finishing.
Carpet installation.
Specialty trades responsible for constructing accessory structures such as garages, carports and decks.
Specialty work performed by a licensed plumber or electrician that falls within the scope of their license.

Expand/collapse How do I know if an installer has a current certification?

Ask to see their card or certificate. Certified manufactured home installers are provided a certificate and wallet card containing their Washington Installer certification number and expiration date.
Contact The Department of Labor & Industries or check the certified installer list available on our Web site.

Certified Installer Tag Requirements

Are certified installers required to post special tags on the M/MH being installed?

Yes. Since July 1, 2003, certified manufactured home installers must place a red metallic installer certification tag on each home they install prior to inspection by the local jurisdiction. The tag must list all installation work performed by the certified installer.
If two or more certified installers perform different aspects of the installation, one tag is required for each installer. Example: If one installer sets the forms and pours the concrete runners and another installer performs all other installation work, there should be two tags affixed to the home.

Who issues installer certification tags?

L&I issues tags only to certified installers.

Where should the installer certification tag be located?

WAC 296-150I-0160 requires installer certification tags to be placed directly above or below the HUD certification label, or temporarily located in plain sight within three feet of the home’s front entry.

Who may remove an installer certification tag?

Installer certification tags shall be removed only by the homeowner following final approval of the installation of the home by the local enforcement agency.

For more information:

RCW 43.22 Sections 335-495 - Manufactured/mobile homes, factory-assembled structures. (apps.leg.wa.gov)
RCW 43.22A - Mobile and Manufactured Home Installation. (apps.leg.wa.gov)
WAC 296-150I - Manufactured Home Installer Training and Certification Program, Installation Code. (apps.leg.wa.gov)
WAC 296-150M - WA Manufactured Home Code. (apps.leg.wa.gov)