Permits Fees & Inspections

About Mobile/Manufactured Homes

What is the difference between a mobile or manufactured or home?

a manufacturered home A manufactured home is a single-family dwelling built according to the Department of Housing and Urban Development (HUD) Manufactured Home Construction and Safety Standards Act, which is a national, preemptive building code.



a manufactured home A mobile home is a factory-built dwelling built prior to June 15, 1976, to standards other than the HUD Code, that were acceptable under applicable state codes in effect at the time of construction or introduction of the home into the state. WAC 296-150M.


Identifying a mobile/manufactured home

A mobile/manufactured home can be identified by one or more of the following:

  • A certification label from HUD attached to the exterior side of the end wall opposite the hitch.

HUD certification label


  • A metallic label (insignia) on the end wall opposite the hitch (or on older units may be next to the front or back door) issued by L&I that is (or was) red. (See examples.)
L&I Alteration Label
New insignia
  L&I Alteration Label (OLD) (F622-030-000)
Old insignia

Some or all of the following components:

  • A steel frame that supports the floor.
  • A data plate ( on the interior of the home that contains the name and address of the manufacturer as well as a statement "or manufactured home is designed to comply with ..." as well as other information. It is usually located near the main electrical panel box, in the laundry area, inside a closet, on a cabinet door in the bathroom, laundry room, or kitchen.
  • A heat loss certificate that specifies the heating zone for which the home was designed as well as other data pertaining to the home.
  • A serial number stamped on the front metal crossmember.
  • A title issued by the Department of Licensing.
  • The furnace and water heater have markings on them specifying that they may be used in manufactured/mobile homes.
  • The main electrical panel box has four (4) wire coming into it.
  • The electric range and electric dryer have four (4) connection points.
  • There are labels on the exterior walls near each of the services (i.e. water inlet, electrical inlet, and sewer drain).

If a home has any of these items, it is a mobile/manufactured home and requires inspections for all alterations by L&I.

More information:

Acrobat PDF file What homeowners and contractors should know when altering a mobile/manufactured home. (627 KB PDF)

Is the home missing HUD labels? (

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