Thread: Flex through CMU

Just trying to clear this up... Can stainless flex be installed thru CMU or concrete? I see that it says no, then refers back to 2414 where stainless is an approved material to pass thru walls. Unless I read this wrong.

G2422.1.2.3 (411.1.3.3) Prohibited locations and penetrations.

Connectors shall not be concealed within, or extended through, walls, floors, partitions, ceilings or

appliance housings.

Exceptions:

1. Connectors constructed of materials allowed for piping systems in accordance with Section G2414 shall be permitted to pass through walls, floors, partitions and ceilings where installed in accordance....

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The key word is "connectors" which are not allowed to pass through walls, floors, etc. Piping systems are allowed to pass through walls and floors.

The IRC defines a connector as follows:

CONNECTOR, APPLIANCE (Fuel). Rigid metallic pipe and fittings, semirigid metallic tubing and fittings or a listed and labeled device that connects an appliance to the gas piping system.

The exception, therefore, appears to pertain to where the materials used for gas piping are also used to connect the appliance to the gas piping system (in effect, the gas is piped directly to the appliance). In your example, this would apply to connecting the CSST gas piping directly to the appliance. However, if the appliance is connected to the gas piping system using a Listed and labeled appliance connector in compliance with ANSI Z21.24 and installed in accordance with the manufacturer’s installation instructions then that appliance connector must be located entirely in the same room as the appliance.

G2422.1 (411.1) should tell you all you need to know about what is approved for connecting appliances.

Thanks CW, Got it.

That looks like an appliance connector to me, but here's Gastite's instructions for CSST through masonry.

4.3.8 Routing Through Masonry Material
“Masonry material” includes but is not limited to brick, concrete, mortar, and stucco. The term “through masonry construction” refers to any enclosed/concealed construction spaces where CSST is routed in close proximity to masonry but does not apply to exposed CSST mounted to a set masonry surface.

When it is necessary to install Gastite/FlashShield through masonry materials the tubing shall be routed through a conduit that is a ½" larger in diameter (to ease routing) than the OD of the CSST and appropriate for the application. The sleeve must maintain a continuous watertight barrier between the masonry material and the CSST, up to or past the edge of the masonry hole.

Masonry encasement refers to any enclosed/concealed construction within “masonry material” that produces distributed loads. For masonry encasement see Underground Installations (section 4.9).