View Full Version : Basement Gas Line Work

11-28-2004, 06:03 AM
I am finishing the basement and need to reroute the gas line. It currently runs across the basement in an area where I do not want a drop ceiling. I am going to move the gas line closer to the centerline of the basement where a soffit will already be necessary to hide the main beam and air conditioning ducts.

In order to remove only the minimum amount of gas pipe, I am going to have to cut the pipe at one or two locations. Before I make the cuts, I want some advice on making sure the gas line has been adequately vented and cleared of gas. First, I plan to close the valve at the meter where the gas enters the house then let the various pilot lights just burn out consuming some of the residual gas in the pipes. Then Iíll remove the couple of plugs that exist in the line and let them vent with the basement windows open and maybe a fan.

Is this sufficient to make it safe to work on the pipes? If not what else do I need to do to vent the pipes?

Also what is the best way to cut the pipes? Sawzall?

Gary Swart
11-28-2004, 09:20 AM
Perhaps some of the licensed plumbers will have more to say about this, but I don't think there is any problem with the small amount of gas that will be in the pipes. However, I'd use a pipe cutter to cut the pipes rather than a recip saw. There could be enough gas lingering to spark if you use the saw. The pipe will be reusable also. If you are not experienced with cutting, threading, and joining pipe, it would be advisable to hire a licensed plumber for this job.

11-28-2004, 12:46 PM
A second word of caution, the main shutoffs at the meter, especially if they haven't been used for awhile, don't always completely shut off the gas (I think that they rely somewhat on grease, and when that gets old and hard it doesn't seal well). I found this out by accident. I shut it off, didn't smell any gas (very small leak through the open pipe connection) closed the door to go get another part, and came back to a basement reeking of gas. Lucky. So, test that the shut off actually shuts off! once you open the pipe up.

11-28-2004, 02:48 PM
Very rare that a gas meter shut off valve does not hold 100%, in fact I have never seen one fail except a possible leak from the packing nut which can be easily tightened.

The questions that you're asking leads me to believe that you do not have any experience whatsoever working on a gas piping system. This type of work definitely requires a knowledgeable person, preferably a licensed plumber.
...There is no room for error.

Bob's HandyGuy
11-29-2004, 01:42 PM
To my way of thinking, since you are opening plugs on the line, even if there was combustion in the pipe it would blow through the opening. I personally would not worry about an explosion. (I did hear about someone cutting an unvented gas pipe with an acetylene torch. It was a salvage job on an old ship. The results were horrific. This was of course, a very large, unvented line with many cubic feet of gas in it.)