Residential gas piping rules

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Most municipalities follow the requirements contained in Chapter 24 of the International Code Council's Residential Building Code (RBC) when it comes to rules for repairing or installing residential gas piping. Installers should also follow the recommendations of appliance manufacturers.

Most local building codes mandate a licensed contractor perform all installation of gas piping.


Section G2401.01 (101) of the Residential Building Code covers the gas piping rules for one- and two-family homes. The regulations start with the point where the gas is delivered all to way to the connection to appliance's shutoff valve. The codes deal with the piping system, including design, materials, components and fabrication. Installers must follow the rules for assembling, installing, testing, inspectiing, maintaining and operating.These rules do not pertain to most of the guidelines for liquid petroleum (LP) piping.

Piping Size

Section G2413 (402) of the Residential Building Code states the gas supply to the appliance must have ample volume to meet the requirements of the appliance. Typically, the appliance manufacturers have specifications for pipe size -- often dependent on British Thermal Unit (BTU) input. This rating commonly applies to furnaces or boilers; most appliances have the BTU input requirements on plates attached to the unit.

Piping Materials

The Residential Building Code (RBC) specifies the type of materials for gas piping systems. It also states that the material not listed in the standards should be approved or "investigated and tested" to verify it is safe and adequate for its intended use. This verification includes recommendations by the appliance manufacturer and by the local building code regulations.

RBC states that. steel and wrought iron pipe must have the Standard weight of Schedule 40 and meet the certain criteria set by American Society of Mechanical Engineers (ASME) or American Society for Testing and Materials (ASTM). Plastic pipe, tubes and fittings must conform to the ASTM standards. The regulation requires to material to have the following markings: "Gas" and "ASTM D 2513." RBC prohibits the use of cast iron pipes.


The RBC has numerous rules regarding installing residential gas piping. For example, the code prohibits putting pipes through ductwork, clothing chutes, chimneys, elevator shafts and other locations. It does not permit installing piping in solid partitions or walls unless enclosed in casings. The regulations also prohibit concealing connections or fittings, such as couplings or unions. In addition, RBC addresses gas pipes installed in trenches, solid flooring underneath buildings and in other locations. Installers must use gas shut-off valves comprised of materials compatible with the piping. The rules also address testing and inspecting piping systems and specifying the type of material to use for connecting appliances to the gas piping system.