Can I cap off a gas line and leave it inside a closed joist space?

Question

I am renovating my kitchen and will be switching from gas stove to induction cooktop. The gas stove is currently hooked up to a 3/4 inch iron pipe coming through the subfloor (below it is a drywalled finished basement). The wall where the old stove is located is coming down, so I cannot have the pipe sticking out.
Can I simply remove the valve, cap it off with a 3/4” iron cap and Rectorseal, and then 1/4 turn the whole assembly at the lower elbow so it is tucked away into the joist space? Or should I remove the pipe down to elbow and cap it with an threaded plug? The subfloor will be patched and then covered with a new hardwood flooring. Thanks.

Eric Stevens · Accepted Answer

Either of the solutions you mention will work, but I recommend, if you have enough room, completely removing the elbow and installing a cap on the horizontal line in the floor. This way there are fewer connections, therefore fewer leak points. Of course, make sure you leak test any joints you move or work on.
There is nothing wrong with a gas line terminating in a floor, other than the difficulty of trying to use it for something in the future. But it's no more dangerous than having any other gas joint in the floor.
The ideal solution would be to find where that branch line begins, and cap it there. That way you remove all potential leaks after the origin point. However, I'm not sure that would be easy for you, as you stated that the basement is drywall-finished.
For your reference, here's a link to Minnesota's gas code. It says nothing about gas line terminations. It mentions that gas valves must be accessible, but that doesn't apply to your situation, as you will be removing the valve.
https://up.codes/viewer/minnesota/mn-fuel-gas-code-2015/chapter/4/gas-piping-installations#4

Can I cap off a gas line and leave it inside a closed joist space?

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