The Washington State Manufactured Home (Mobile Home) Installation Standards as set forth in the Washington Administrative Code (WAC) Section 296-150M is adopted by reference in Section 14.04.040.
(Ord. 224 (1998) § 12.1, 1998; Ord. 323 (2004) § 110, 2004)
Appendix AE of the International Residential Code as adopted in Section 14.04.599 is amended as follows:
A. 
IRC Appendix E, Section AE101.1 is amended as follows:
AE101.1 General. These provisions shall be applicable only to a manufactured home used as a single dwelling unit installed on a lot and shall apply to the following:
1.
Construction, alteration and repair of any foundation system which is necessary to provide for the installation of a manufactured home unit.
2.
Construction, installation, addition, alteration, repair or maintenance of the building service equipment which is necessary for connecting manufactured homes to water, fuel, or power supplies and sewage systems.
3.
Alterations, additions or repairs to existing manufactured homes. The construction, alteration, moving, demolition, repair and use of accessory buildings and structures and their building service equipment shall comply with the requirements of the codes adopted by this jurisdiction.
These provisions shall not be applicable to the design and construction of manufactured homes and shall not be deemed to authorize either modifications or additions to manufactured homes where otherwise prohibited.
Exception: In addition to these provisions, new and replacement manufactured homes to be located in flood hazard areas as established in
Table R301.2(1) of the International Residential Code shall meet the applicable requirements of Sections R322 of the International Residential Code.
B. 
IRC Appendix E, Section AE102.2 is amended as follows:
AE102.2.2 Additions, alterations or repairs. Additions made to a manufactured home shall conform to one of the following:
1.
Be certified under the National Manufactured Housing Construction and Safety Standards Act of 1974 (42 U.S.C. Section 5401, et seq.).
2.
Be designed and constructed to conform with the applicable provisions of the National Manufactured Housing Construction and Safety Standards Act of 1974 (42 U.S.C. Section 5401, et seq.).
3.
Be designed and constructed in conformance with the code adopted by this jurisdiction.
Additions shall be structurally separated from the manufactured home.
C. 
IRC Appendix E, Section AE102.3 is deleted and not adopted.
D. 
IRC Appendix E, Section AE102.5 is deleted and not adopted.
E. 
IRC Appendix E, Section AE104.2 is amended as follows:
AE104.2 Additions, alterations and repairs to a manufactured home. A permit shall first be obtained from the Washington State Department of Labor and Industries to alter, remodel, repair or attach accessory buildings or structures to a manufactured home subsequent to its initial installation. Permit issuance and fees therefore shall be in conformance with the codes applicable to the type of work involved.
An addition made to a manufactured home as defined in these provisions shall comply with these provisions.
F. 
IRC Appendix E, Section AE105.1 is amended by adding additional paragraphs as follows:
Pursuant to RCW 19.27.095 and RCW 19.27.097, and in addition to the requirements above, no building permit application shall be complete unless or until evidence of an adequate water supply and evidence of an adequate sewage disposal system for the intended use of the building is provided from an approved agency for structures where plumbing fixtures are part of the proposed building permit application.
Evidence shall be by either A or B below:
A.
Upon building permit application, where parcels are serviced by on-site sewage disposal systems, an accepted building site application* or an accepted building clearance is required for:
1.
New manufactured home installations.
2.
Additions where there is an increase in the floor area which extends beyond the original exterior walls.
3.
Alteration or remodeling where the total number of bedrooms is increased.
4.
Change in use which results in an increase in the water/sewage volume or potential health risk.
*
An application may be submitted with a preliminary building site application, which may be obtained from the health district. However, until an accepted building site application is received from the health district, a building permit application will not be complete.
B.
Upon building permit application, a sewer permit and an accepted building clearance are required for the installation of a manufactured home unit.
G. 
IRC Appendix E, Section AE107.1 is amended as follows:
AE107.1 Permit Fees. The fee for each manufactured home installation permit shall be established by resolution.
H. 
Section AE107.2 is deleted and not adopted.
I. 
Section AE107.3.3 is deleted and not adopted.
J. 
Section AE108.5.1 is amended as follows:
AE108.5.1 Structural inspections for the manufactured home installation.
The building official, upon notification from the permit holder or the permit holder’s agent, shall make the following inspections and shall either approve that portion of the construction as completed or shall notify the permit holder or the permit holder’s agent wherein the same fails to comply with these provisions or other applicable codes.
A.
Reinforcing steel or structural framework of any part of a manufactured home foundation system specifically designed by an engineer registered in the State of Washington, shall not be covered or concealed without first obtaining the approval of the building official.
1.
Foundation Inspection: To be made after excavations for footings are completed and any required reinforcing steel is in place. For concrete foundations, any required forms shall be in place prior to inspection. All materials for the foundation shall be on the job, except where concrete from a central mixing plant is to be used, (ready-mixed) the concrete materials need not be on the job.
2.
Concrete Slab or Under-Floor Inspection: To be made after all in-slab or underflow building service equipment, conduit, piping accessories and other ancillary equipment items are in place but before any concrete is poured or the manufactured home is installed.
B.
Anchorage Inspection: To be made after the manufactured home has been installed and permanently anchored.
K. 
IRC Appendix E, Section AE305.6 is amended by adding an additional paragraph as follows:
Manufactured homes or their accessory buildings shall not be used or occupied until a certificate of occupancy is issued in accordance with Section R110 of this code.
L. 
IRC Appendix E, Section AE501.1 is amended as follows:
AE501.1 General. A manufactured home shall be installed on a foundation system which is designed and constructed in accordance with the manufacturer’s installation instructions.
Exception: When specifically authorized by the building official, foundation and anchorage systems which are constructed in accordance with the methods specified in Section AE600 of these provisions, or in the United States Department of Housing and Urban Development Handbook, Permanent Foundations For Manufactured Housing, 1984 Edition, Draft, shall be deemed to meet the requirements of this Appendix E.
M. 
IRC Appendix E, Section AE504.1 is amended as follows:
AE504.1 General. Accessory buildings shall not be structurally supported by or attached to a manufactured home unless engineering calculations are submitted to substantiate any proposed structural connection and all alterations to the manufactured home are approved by the Washington State Department of Labor and Industries.
Exception: The building official may waive the submission of engineering calculations if it is found that the nature of the work applied for is such that engineering calculations are not necessary to show conformance to these provisions.
N. 
IRC Appendix E, Section AE120.1, is amended as follows:
AE120.1 General. Sections AE121 through AE125 are applicable only when specifically authorized by the building official for use when specific installation instructions from the manufacturer of the manufactured home are not available.
(Ord. 224 (1998) § 12.2, 1998; Ord. 323 (2004) § 111, 2004; Ord. 391 (2007) § 37, 2007; Ord. 440 (2009) § 20, 2009; Ord. 638 (2025) § 26, 2025)