4-5-090 INTERNATIONAL MECHANICAL CODE ADOPTED:

A. ADOPTION:

The 2021 Edition of the International Mechanical Code (IMC), as adopted and amended by the State Building Code Council in chapter 51-52 WAC, as published by the International Code Council, is adopted by reference with the following additions, deletions and exceptions: Provided, that Chapter 1, Scope and Administration, is not adopted and the Construction Administrative Code, as set forth in RMC 4-5-060, shall be applied in place of IMC Chapter 1, Scope and Administration. Provided, that the installation of fuel gas distribution piping and equipment, fuel gas-fired appliances and fuel gas-fired appliance venting systems shall be regulated by the 2021 International Fuel Gas Code. Provided, that detached one- and two (2) family dwellings and multiple single-family dwellings (townhouses) not more than three (3) stories high with separate means of egress and their accessory structures not more than three (3) stories above grade plane in height shall comply with the International Residential Code. Provided, that the standards for liquefied petroleum gas installations shall be the 2020 Edition of NFPA 58 (Liquefied Petroleum Gas Code) and the 2021 Edition of ANSI Z223.1/NFPA 54 (National Fuel Gas Code). References in this code to Group R shall include Group I-1, Condition 2 assisted living facilities licensed by Washington State under chapter 388-78A WAC and Group I-1, Condition 2 residential treatment facilities licensed by Washington State under chapter 246-337 WAC. (Ord. 6133, 3-4-2024)

B. EXCEPTIONS:

The provisions of this code do not apply to temporary growing structures used solely for the commercial production of horticultural plants including ornamental plants, flowers, vegetables, and fruits. “Temporary growing structure” means a structure that has the sides and roof covered with polyethylene, polyvinyl, or similar flexible synthetic material and is used to provide plants with either frost protection or increased heat retention. A temporary growing structure is not considered a building for purposes of this code.

C. CONFLICTS:

In the case of conflict between the duct sealing or insulation requirements of Section 603 or 604 of this code and the duct sealing or insulation requirements of chapters 51-11C and 51-11R WAC, the Washington State Energy Code shall govern. (Ord. 4546, 7-24-1995; Amd. Ord. 5085, 6-21-2004; Ord. 5157, 9-26-2005; Ord. 5450, 3-2-2009; Ord. 5676, 12-3-2012; Ord. 5710, 4-14-2014; Ord. 5810, 7-11-2016; Ord. 6010, 1-25-2021)