Black pipe in residential homes is used for gas supply to stoves, water heaters, etc. The pipe itself is sold in pre-cut lengths from a few inches to several feet and has a thread on each end. The thread is tapered so that it is thinner at the end of the pipe. This helps to seal the joint when connected to a coupling, reducing the possibility of leaks. Though possible to thread pipe, professional tools are needed. However, many home improvement stores offer this service, both cutting and threading the pipe to length.
Things You'll Need
- Tape measure
- Gas pipe and couplings
- Thread compound
- Pipe wrench
- Gas shut-off valve
- Water spray bottle and soapy water
Measure the entire length of the run of gas pipe. Take note the type of couplings needed (straight, 45-degree, 90-degree, etc.), and where they will be located in the gas line. Be as accurate as possible when measuring each needed length of pipe. Double-check all measurements before buying the gas pipe.
Turn off the gas supply at the house's gas meter. Start at the existing gas supply pipe and work your way one piece of pipe at a time.
Cover the first thread with thread compound and screw it by hand into place. When it is fully hand-tight, tighten it with a pipe wrench but no more than two turns--more may damage the threads.
Apply thread compound to the other end of the pipe and thread on the required coupling. Tighten it with the wrench. Brace the pipe to floor joists or wall studs as you go. Continue in like fashion installing new pipe and couplings, until you reach the gas fixture. Apply compound to the last thread and thread on a gas shut-off valve. Tighten it with the wrench and turn the valve handle to "off".
Turn on the gas and fill a water spray bottle with soapy water. Spray each joint to check for any leaks.