Yes. A homeowner may do installation work on their own residence. The homeowner may have friends or family help with the installation, provided they are not paid to do the work. If the homeowner pays anyone to do any part of the installation work, that person must be certified.
Q: Are homeowners who perform installation work on their own residence required to obtain and post an installer certification tag?
A: No. Homeowners are exempt from the installer certification tag requirement provided:
RCW 43.22 Sections 335-495 - Manufactured/mobile homes, factory-assembled structures.
RCW 43.22A - Mobile and Manufactured Home Installation.
WAC 296-150I - Manufactured Home Installer Training and Certification Program, Installation Code.
WAC 296-150M - WA Manufactured Home Code.