Gas Piping Inspection

Gas piping in residential applications is typically black steel. Galvanized steel can be used, however, it is more expensive and not necessary. Seamless steel, copper and aluminum alloy tubing are allowed with gases and are not corrosive to the piping materials.

Aluminum alloy tubing is not to be used on the exterior or underground. Corrugated stainless steel tubing (CSST) should comply with performance requirements of Standard Fuel Piping Systems.

Plastic pipe, tubing, and fittings are for underground use only and should conform to Standard Specification for Thermoplastic Gas Pressure Pipe and Fittings. Piping should be marked “gas” and “ASTM D 2513.”

Interior gas piping should not be installed through a circulating air duct, clothes chute, gas vent, ventilating duct, or dumbwaiter or elevator shaft.

An individual gas shut off valve should be present at each appliance, or no further than 6' maximum, visible and accessible.

Sediment Traps, sometimes referred to as drip legs, are commonly required to be present and immediately upstream of the shut off valve. The idea being any debris will be trapped in the 'leg' before it's able to reach the gas shut off valve.

The above ground portion of the gas piping system, upstream from the equipment shutoff should be bonded to a grounding electrode. The gas piping is not to be used as a grounding electrode.

Home inspectors do not check gas pressure, however, testing should not be more than 1 ½ times the maximum working pressure and not less than 3 psig for 10 minutes.

Unvented/ventless room heaters are not to be installed in bathrooms or bedrooms. Check with your local government, as many communities have restrictions in place and do not allow any unvented or ventless type heating systems to be present inside a residence.